A testing machine is only as good as its hold on the specimen. A jaw that slips, a fixture out of alignment or a clamp that bites too hard will end the test early and leave the material carrying the blame. NextGen supplies grips and fixtures matched to both the specimen and the frame, for tension, compression, flexure, peel, tear and shear, working to ASTM E8 and ASTM D882.
The range covers wedge, pneumatic, self-tightening, roller and threaded grips, three-point and four-point bend fixtures, compression platens and specialised tooling for wood, composites, wire and cable, sized from a few newtons up to the full capacity of a hydraulic frame. Fixtures arrive fitted to your machine, and support continues for the life of the equipment.
The catalogue below holds 20 families and 163 individual models, grouped by what the tooling does. Jump straight to the group you need:
Tensile Grips
Every grip in this group holds a specimen and pulls it, and the choice between them comes down to two questions: how the jaws close, and what the specimen would do if they closed the wrong way. Capacities across the eight families run from 20 N to 300 kN.
There are three ways of closing. Side action grips are tightened by hand with screws or levers and take interchangeable jaw faces - smooth, serrated or rubber-coated - which makes them the general-purpose choice for plastics, metals, textiles, rubber and composites. Pneumatic grips close on air pressure at a button or foot pedal, applying the same clamping force to every specimen in a series. Wedge, self-tightening and eccentric roller grips close themselves: the tensile load drives a wedge, a cam or a roller that grips harder as the pull rises, which is what keeps an elastomer or a thin film from creeping out of the jaws as it stretches and thins.
Two families are chosen by the shape of the specimen rather than by the mechanism. Snubbing grips wrap wire, rope or cable several times around a capstan, so friction spreads the load along its length instead of concentrating it at the jaw. Threaded grips engage a bolt, screw, stud or nut by its own thread, and shoulder fixtures hold a specimen by an enlarged end, flange or head that ordinary jaws cannot take - the setup for pull-off, push-out and component integrity tests.
12 models
Maximum force capacity: 2 kN to 100 kN
Wire and cable snubbing grips - also referred to as capstan or bollard grips - are specialized fixtures for tensile testing of wires, ropes, fiber bundles, and electrical cables with high slip risk. These grips use a curved mandrel or capstan around which the specimen is wrapped multiple times to generate friction and distribute the load evenly across its length.
This design prevents localized failure at the jaw and allows accurate measurement of the specimen’s full tensile strength, especially for high-strength steel cables, braided wires, and reinforced conductors. The free end is typically secured using a clamp or wedge, ensuring stable loading throughout the test.
These grips are essential for test laboratories, cable manufacturers, and infrastructure or construction quality control teams requiring compliance with ASTM, ISO, or other international standards for cable and wire testing. They offer a non-damaging, high-holding solution for tensile testing of flexible yet high-capacity specimens.
See all 12 snubbing grips
11 models
Maximum force capacity: 500 N to 100 kN
Pneumatic grips use air pressure to apply quick, uniform, and adjustable clamping force to test specimens. Activated by a button or foot pedal, these grips feature built-in air cylinders that close the jaws with precisely controlled pressure - ideal for testing materials that require consistent gripping without surface damage.
They are widely used for rubber, plastics, textiles, and other soft or flexible specimens where accurate pressure control is essential. Users can fine-tune the clamping force to prevent slippage or crushing, especially during standardized tensile tests.
Thanks to their fast operation, pneumatic grips are preferred in high-throughput testing laboratories, quality control departments, and manufacturing facilities. Variants like pneumatic side-action grips are commonly used for mid-range force applications up to 20 kN, offering repeatable and self-centering clamping across different test setups.
These grips support a wide range of material tests and can be adapted to meet requirements from ASTM, ISO, and other international standards, ensuring consistent, safe, and efficient performance in demanding test environments.
See all 11 pneumatic grips
9 models
Maximum force capacity: 20 N to 20 kN
Side action grips are versatile mechanical clamps designed for tensile testing of plastics, metals, textiles, rubber, and composite specimens. These manually operated grips apply lateral pressure through dual jaws, tightened using screws or levers, to hold the specimen securely without causing surface damage.
Ideal for medium-load tensile applications, side action grips are commonly used in quality control and research environments. They are especially valued for their adaptability - interchangeable jaw faces (smooth, serrated, rubber-coated) allow precise matching to different material types and surface conditions, helping reduce slippage during testing.
This type of grip is a cost-effective and reliable choice for laboratories performing standardized tensile tests across a wide range of specimen geometries, where firm, controlled clamping is required without the complexity of powered gripping systems.
See all 9 side action grips
9 models
Maximum force capacity: 10 kN to 300 kN
Wedge tensile grips use a self-tightening wedge-action mechanism that increases clamping force as tensile load rises. Each grip includes an internal wedge-shaped slider with serrated or knurled jaws that grip the specimen more firmly as tension is applied.
These grips are ideal for high-strength materials such as metals and composites, particularly in high-load testing applications. Their design ensures secure holding without slippage or jaw damage, even under peak loads. Available in both manual and hydraulic configurations, wedge grips accommodate a wide force range - from a few kilonewtons to over 500 kN.
They are commonly used in material testing laboratories, aerospace and automotive industries, and research institutions performing ASTM E8, ISO 6892, or other metal tensile tests. The grips maintain axial alignment during testing, making them essential for precise tensile strength measurements of hard, structural specimens.
See all 9 wedge grips
5 models
Maximum force capacity: 1 kN to 5 kN
Shoulder fixtures - also known as shoulder grips or ledge grips - are specialized testing accessories designed to hold specimens with an enlarged end, flange, or head that cannot be gripped using standard jaws. These fixtures are essential for performing pull-off, push-out, and component integrity tests where force must be applied through the specimen’s shoulder to simulate real-world use conditions.
Common applications include testing bolt heads, cable terminations, syringe plungers, anchors, buttons, bottle caps, and fastener pull-outs. The specimen typically rests on a recessed ledge or collar, while the opposing end is subjected to axial force by the UTM.
Shoulder fixtures are widely used in medical device testing, automotive component validation, packaging durability, and construction anchoring systems, where it’s critical to assess how parts behave under tensile or compressive loads applied through their structural features. Built in various sizes and configurations, these grips ensure even load distribution across the shoulder area, preventing bending and enabling accurate, repeatable test results in accordance with ASTM and ISO standards.
See all 5 shoulder fixtures
3 models
Maximum force capacity: 500 N to 1 kN
Eccentric roller grips are self-tightening fixtures specifically designed for tensile testing of thin films, rubber sheets, flexible plastics, and other delicate or low-strength materials. They feature an off-center cam roller that clamps the specimen against a fixed anvil. As the tensile load increases, the roller rotates further, automatically increasing the grip force.
This self-energizing mechanism ensures that even as the specimen elongates or necks, it remains securely held without slippage or tearing. To protect sensitive materials, the gripping surfaces are often coated with rubber or non-cutting materials.
These grips are ideal for R&D labs, quality control environments, and manufacturers working with soft or flexible specimens. Their tool-free, lever-actuated design allows for quick specimen loading while maintaining stable clamping pressure throughout the test. Eccentric roller grips comply with relevant ASTM and ISO standards for elastomer and film testing, ensuring accurate and repeatable results.
See all 3 roller grips
2 models
Maximum force capacity: 2 kN to 5 kN
Self-tightening grips are designed to automatically increase clamping pressure as tensile force is applied, making them ideal for materials that elongate, thin, or deform during testing. Commonly used for elastomers, thin plastics, foams, fabrics, and biomedical specimens, these grips adapt to changing specimen dimensions without manual adjustment.
Popular designs include scissor grips, eccentric cam grips, and lever-action jaws, all of which tighten progressively under load. This mechanism minimizes slippage, eliminates the need for excessive pre-tightening, and prevents damage to delicate specimens at the start of the test.
These grips are well-suited for quality control laboratories, textile and rubber manufacturers, and research environments conducting standardized tensile tests on soft, elastic, or low-friction materials. They improve test repeatability and maintain reliable alignment and gripping force throughout the loading cycle.
See both self-tightening grips
2 models
Maximum force capacity: 100 kN to 300 kN
Bolt and nut tensile grips (also known as threaded grips) are specialized fixtures for axial tension testing of bolts, screws, studs, and nuts. These grips use threaded adapters or holders rather than clamping jaws, allowing direct engagement with the specimen's threads. The setup replicates real-world loading conditions by applying tensile force through the bolt head and nut.
These grips are essential for measuring the tensile strength, yield behavior, and proof load capacity of fasteners, in accordance with standards such as ASTM F606. In a typical proof load test, a nut is mounted on a hardened test mandrel and loaded to a specified tension to verify thread integrity and load-bearing capacity without failure. NextGen’s grips include interchangeable threaded inserts to accommodate various thread sizes.
Widely used in automotive, aerospace, construction, and mechanical engineering laboratories, these grips are built from high-strength steel to handle forces exceeding 100 kN. They enable reliable, repeatable testing of threaded fasteners and provide critical data for quality control and product certification in structural and mechanical applications.
See both threaded grips
Flexural and Compression Fixtures
These fixtures support a specimen and press on it. What separates them is how the load is introduced and how much of it the frame has to carry: this group spans 2 kN to 2000 kN.
In a three-point test a single nose presses at midspan, which is the direct route to flexural strength, modulus of elasticity and modulus of rupture. A four-point fixture applies two evenly spaced loads instead, creating a constant moment region between them and removing shear from the middle of the specimen. That is the configuration for brittle materials, composites and concrete beams, where a stress concentration under a single nose would decide where the specimen breaks. Both types use lower support anvils and upper loading noses or rollers with adjustable spans, and both are built to meet ASTM D790, ASTM C393, ASTM D6272 and ASTM C78.
Compression fixtures work the other way round: flat, precision-machined platens spread an axial load evenly across the specimen face. The heavy end of the group belongs to hydraulic frames, where the heavy-duty bending and precision flexure fixtures carry up to 2000 kN for structural work on metals, ceramics and construction materials.
8 models
Maximum force capacity: 10 kN to 300 kN
Bending fixtures - also known as flexural test fixtures - are used with universal testing machines to perform 3-point and 4-point bend tests. These tests evaluate flexural strength, modulus of elasticity, and modulus of rupture in materials such as plastics, metals, wood, and composites.
The fixtures consist of lower support anvils and upper loading noses (or rollers), with adjustable spans to accommodate different specimen sizes and geometries. They are engineered to meet test requirements defined by standards such as ASTM D790 for plastics and ASTM C393 for sandwich structures. The design ensures precise alignment and minimal friction or torsion during loading.
Manufacturers, research facilities, and testing labs use bending fixtures to simulate real-world flexural stress scenarios under controlled conditions. Constructed from high-strength steel or rigid aluminum, these fixtures maintain structural integrity even under high loads, ensuring that force is applied directly to the specimen without deflection or misalignment.
See all 8 bending fixtures
8 models
Maximum force capacity: 20 kN to 100 kN
3-point and 4-point bending fixtures are specialized tools used in flexural testing to apply two evenly spaced loads across a specimen, creating a constant moment region between the load points. This configuration eliminates shear forces in the central section, enabling accurate measurement of flexural modulus and modulus of elasticity.
These fixtures are particularly suited for testing brittle materials, plastics, composites, and concrete beams, where minimizing stress concentration is essential. Typical applications include tests based on ASTM D6272 for plastics and ASTM C78 for third-point loading of concrete specimens.
The fixture consists of two upper loading rollers and two lower supports with adjustable span distances to accommodate different specimen sizes and meet specific standard requirements. It is widely used by construction material labs, composite manufacturers, and research institutions aiming to observe failure modes or deflection behavior under pure bending conditions.
See all 8 uniform moment fixtures
7 models
Maximum force capacity: 2 kN to 300 kN
Compression fixtures are essential accessories for universal testing machines used to apply axial compressive loads in a stable and aligned manner. The standard configuration includes flat compression platens - precision-machined steel plates that ensure even force distribution across the specimen surface.
For high-precision or high-force testing, one platen may feature a spherically seated base to self-align with the specimen, reducing the risk of eccentric loading and improving result accuracy. Additional configurations include compression cages or four-post assemblies for testing large samples like foam blocks, packaging materials, or structural components, ensuring specimens do not buckle or shift during loading.
NextGen's compression fixtures are available in a range of sizes and capacities, suitable for testing plastics (ASTM D695), concrete cubes, metals, composites, and paperboard products. These fixtures are ideal for materials testing laboratories, construction quality control, and packaging validation, providing a rigid, compliant platform for reliable compressive strength measurements.
See all 7 compression fixtures
2 models
Maximum force capacity: 2000 kN
NextGen offers a specialized range of flexure fixtures designed for accurate high-force flexural testing of metals, ceramics, composites, and construction materials. Compatible with hydraulic universal testing machines, these fixtures meet rigorous standards such as GB/T 2542, GB/T 4111, GB/T 50081, and JC/T 239, providing reliable performance for industrial, academic, and quality control applications. With maximum capacities up to 2000 kN, these fixtures are built to handle demanding flexural evaluations, from single-point to four-point test configurations.
Engineered with adjustable span ranges and precision alignment, NextGen’s flexure fixtures accommodate many specimen sizes and shapes. Models in this category support standard specimen formats (e.g., 150×150×600 mm, 100×100×400 mm) and allow integration of optional digital indicators to measure elastic modulus. Whether you're testing concrete beams, laminated composites, or advanced ceramics, these fixtures deliver accurate, repeatable results in ambient conditions.
Two fixtures cover the range, and the load rating is not what separates them: both are rated to 2000 kN. The span is. The first works on roller supports for three- and four-point bending of metal, ceramic and composite bars.
See both flexure fixtures
1 model
Maximum force capacity: 2000 kN
NextGen’s line of heavy-duty bending fixtures is engineered for high-force testing applications involving metals, composites, and ceramics. Designed specifically for hydraulic universal testing machines, these fixtures support complex bending evaluations at forces up to 2000 kN, making them suited to structural testing in automotive, aerospace, construction, and research environments. Each fixture is developed in compliance with GB/T 232, GB1499.1, and GB1499.2, for accurate, repeatable testing in accordance with international standards.
These fixtures accommodate many mandrel diameters and support test spaces of up to 480 mm, with secure fixing blocks and positioning pin connections for enhanced stability. Whether conducting flexural analysis of reinforcing bars, composite layers, or advanced ceramics, this category offers reliable solutions for demanding bending evaluations.
One fixture covers the range, and what changes from test to test is the mandrel. The body is rated to 2000 kN and needs 480 mm of test space; four mandrel diameters come with it, and the rest are listed in the second table.
See the heavy-duty bending fixture
Material-Specific Grips and Fixtures
Sometimes the material decides the tooling, not the test. These four families exist because a standard jaw would either damage the specimen or load it in a way that says nothing about how it behaves in service. Together they cover 200 N to 2000 kN.
Composites fail in ways a metal coupon does not - delamination, shear between plies, premature failure at a stress concentration - so their fixtures are built to hold laminates without crushing them and to keep the load aligned. This is the largest family in the catalogue. Wood is anisotropic and variable, and its fixtures follow ASTM D143 and ASTM D4761 across tensile, shear, compression, nail and screw withdrawal, and flexural tests.
The other two sit at opposite ends of the force range. Tear, peel, puncture, pull-through and buckle tests need tooling that conventional grips cannot provide and are usually run on thin, soft material. The splitting fixtures take rock, concrete and composite specimens up to 2000 kN in geotechnical, mining and structural laboratories.
31 models
Maximum force capacity: 200 N to 100 kN
Composite grips and fixtures are engineered for the complex mechanical testing of composite materials, including carbon fiber reinforced polymers, fiberglass, and laminates. These materials require specialized handling to avoid premature failure, misalignment, or stress concentrations during testing.
For tensile testing, hydraulic wedge grips with treated jaw surfaces are used to prevent slippage or crushing of composite laminates. In compression testing, fixtures such as the Combined Loading Compression (CLC) and IITRI types hold specimens with side supports or end tabs to ensure proper failure modes.
Shear testing of interlaminar strength is typically performed using short-beam shear fixtures (per ASTM D2344), Iosipescu shear fixtures (ASTM D5379), and rail shear devices (ASTM D7078) for in-plane shear. Fracture toughness evaluation includes double cantilever beam fixtures (ASTM D5528) for Mode I and end notch flexure or mixed-mode bending fixtures for Mode II delamination.
Additional solutions include picture frame fixtures and bias extensometer setups for fabric in-plane shear, as well as floating roller peel (ASTM D3167) and climbing drum peel fixtures (ASTM D1781) for testing bonded laminate assemblies.
See all 31 composite fixtures
16 models
Maximum force capacity: 500 N to 100 kN
Special-purpose grips and fixtures cover a wide range of non-standard mechanical tests including peel, tear, puncture, pull-through, buckle, and custom shear testing. These solutions are designed for materials and configurations that cannot be tested using conventional grips, allowing flexible adaptation to specialized requirements.
Examples include 90-degree peel fixtures and climbing drum peel fixtures for adhesive bond strength testing of tapes, laminates, and bonded assemblies. Tear test grips hold plastic films or fabrics for propagation tear evaluation. Puncture fixtures include systems for geomembranes under ASTM D4833 and ball burst tests for textiles in accordance with ASTM D3787. Other options include tear propagation fixtures, eyelet pull-through grips, and buckle test fixtures.
Custom shear fixtures are available for adhesive lap joint testing, such as those conforming to ASTM D4501. These solutions are commonly used by packaging developers, textile manufacturers, material testing labs, and industrial product engineers requiring accurate test configurations beyond standard tensile or compression applications.
See all 16 specialized fixtures
6 models
Maximum force capacity: 500 N to 10 kN
Wood testing grips and fixtures are specially designed to accommodate the anisotropic, variable nature of wood and timber specimens. These solutions support a full range of mechanical tests defined by standards such as ASTM D143 and ASTM D4761, covering tensile, shear, compression, nail/screw withdrawal, and flexural testing.
For tensile tests parallel to grain, grips with flat or serrated jaws or shouldered clamps are used to hold dogbone-shaped specimens without crushing. For perpendicular-to-grain tests, fixtures with bonded metal brackets are applied. Block shear fixtures allow testing of shear strength along the grain under tension or compression. Nail and screw withdrawal fixtures are designed to pull fasteners axially from wood blocks to assess withdrawal resistance.
Compression testing is performed using oversized or self-aligning compression platens, while 3-point and 4-point bending fixtures are used for measuring modulus of rupture and modulus of elasticity in lumber and beams.
These fixtures are widely used by wood product manufacturers, construction material testing labs, and furniture and fastener industries, ensuring accurate, repeatable testing while compensating for wood’s natural variability. All fixtures are built to prevent grip-induced failure and ensure compliance with wood testing standards.
See all 6 wood testing fixtures
1 model
Maximum force capacity: 2000 kN
NextGen’s category of high-capacity splitting fixtures is engineered for shear and splitting tests on rock, concrete, and composite specimens. These fixtures are purpose-built for use with hydraulic universal testing machines in demanding environments such as geotechnical labs, mining research centers, and structural materials testing facilities. Designed for compatibility with international standards like GB/T 23561.11, they ensure precise and repeatable performance under loads up to 2000 kN or more.
Each fixture in this category features rugged construction, secure mounting systems (including flanges and positioning pins), and flexible specimen accommodation - supporting standard sizes such as Φ50×50 mm and 50×50×50 mm. Whether testing natural rock or engineered composites, these solutions provide the mechanical stability and test consistency required for accurate material analysis.
The line is built around a single fixture rated to 2000 kN. What decides whether it fits your lab is not the load alone but the mounting and the specimen: it hangs from a flange at the top and a positioning pin at the bottom, needs 450 mm of test space, and takes cylindrical or cubic samples at the sizes given in the table.
See the splitting fixture
Hydraulic and High-Capacity Systems
Servo-hydraulic frames pull harder than mechanical grips can hold, and their tooling is sized and mounted to match. These three families cover 100 N to 2000 kN.
The TestStar® series is matched to NextGen’s own hydraulic machines: the same functions as the standard grips, but built to TestStar mounting, force capacity and control specifications. The dual-action hydraulic grips combine parallel hydraulic clamping with wedge self-tightening, so flat or wide specimens are closed evenly from both sides without bending stress, while the wedge mode adds holding force as the load rises.
The general hydraulic family covers side-acting and wedge grips for straight pulls on metal coupons and bars, together with tensile shear and nut proof load fixtures. Between them these three reach 2000 kN and serve standard tension tests such as ASTM E8 for metals and ASTM A370 for rebar, as well as fastener proof tests to ASTM F606.
13 models
Maximum force capacity: 100 N to 300 kN
TestStar® series grips and fixtures are designed specifically for use with NextGen’s TestStar universal testing machines, which are high-performance systems equipped with hydraulic actuation. These accessories offer the same core functionality as standard grips but are fully compatible with TestStar mounting, force capacity, and control systems.
The range includes manual and pneumatic snubbing grips for testing wires and cables using the capstan method, side action grips for general-purpose tensile testing, wedge-action grips for high-strength metals, and dedicated compression and bending fixtures. Fixtures such as 3-point flexural setups are available for testing plastics, metals, and composites, utilizing the full capabilities of the TestStar frame.
These grips are ideal for test laboratories, heavy industrial applications, and materials R&D, particularly when working with large specimens or high-force testing requirements. Hydraulic variants are available for high-capacity setups.
See all 13 TestStar® grips
9 models
Maximum force capacity: 600 kN to 2000 kN
Within the hydraulic machine accessories category, the tensile grips and fixtures segment covers all devices for applying tension using a high-force system. This includes large hydraulic grips - both side-acting and wedge types - for straight-pulling of metal coupons or bars. It also encompasses special tensile fixtures like the tensile shear fixture, which may be used to test shear strength in tension (for example, pulling on a single-lap joint to induce shear failure), and proof load fixtures for nuts, as commonly needed in fastener testing.
A nut proof load fixture usually involves a loading mandrel (a hardened threaded rod) that the nut is fastened onto, paired with a support so the nut can be pulled without movement. The nut is stressed in tension via the mandrel up to a specified force to ensure it can hold that load without stripping. In the hydraulic context, these fixtures are built to withstand very high forces, since large nuts and fasteners can require hundreds of kilonewtons in proof tests. Tensile grips for hydraulic machines also often feature quick-change jaw inserts and heavy-duty construction, such as bolt grips with larger thread sizes or split collar grips for large diameter specimens.
Everything in this category is about handling large tensile forces safely and accurately. The fixtures are designed to maintain perfect alignment in the vertical direction, as off-axis loads at high force can be catastrophic. With NextGen’s tensile grips and fixtures for hydraulic frames, users can perform standard tension tests (like ASTM E8 for metals, ASTM A370 for rebar, etc.) and specialized tension-based tests (fastener proof tests, shear in tension, etc.) with confidence that the equipment can handle the load. Each fixture meets the relevant standard (such as wedge grips fulfilling the grip requirements of ASTM E8, or nut testers meeting ASTM F606) and interfaces properly with the high-capacity load cells and actuators of the hydraulic machine.
See all 9 hydraulic grips
8 models
Maximum force capacity: 100 kN to 2000 kN
Dual side action/wedge hydraulic grips are designed for high-capacity tensile testing, combining parallel hydraulic clamping with wedge-action self-tightening. In side-action mode, the jaws close symmetrically from both sides using hydraulic pressure, ensuring even, balanced force on flat or wide specimens without introducing bending stress.
The wedge-action mode uses angled jaw slides that increase clamping force as tensile load rises. This mechanism provides additional holding strength for large metal specimens, steel rods, and fasteners, making these grips ideal for testing applications involving forces in the hundreds of kilonewtons. The hydraulic actuation allows pre-set pressure control for safe and consistent specimen engagement.
These grips are commonly used on servo-hydraulic universal testing machines in construction materials labs, metal testing facilities, and industrial manufacturing environments, where conventional manual or pneumatic grips are insufficient. Their robust construction supports maximum machine loads, making them essential for rebar, bolt, and structural metal testing.
See all 8 dual-action grips
Which grip or fixture fits your specimen?
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