Axial Extensometer – Model 3542

General purpose strain gage extensometers for axial tensile, compression, and cyclic testing. Gauge lengths from 20 to 80 mm (and 0.8 to 2 inches) and full scale measuring ranges from 5% to 100% strain.


provides higher measuring ranges with much shorter extensometer arm lengths – all with much greater low strain performance.


to the materials testing community, you know we will be there to stand behind our products when your critical application requires it.

Operation of these, and all of Epsilon’s extensometers, are


using in-house calibration systems that are calibrated with Epsilon’s laser interferometer system.

These extensometers are designed for testing a wide range of materials, including metals, plastics, composites and ceramics. All will perform both tension and compression strain measurement. The dual flexure design makes them very rugged and insensitive to vibrations, which permits higher frequency operation.

They come standard with Epsilon’s quick attach kit, making it possible to mount the extensometer on the test specimen quickly and easily with one hand. The quick attach kit can be removed, allowing mounting of the extensometer with springs or rubber bands.

Model 3542 extensometers are applicable for testing with the following standards:
• ISO 6892-1, 527-2, 527-4, 527-5, 10113
• ASTM E8, E9, D3039, D638, A370, D3552, E517, E646

Model 3542 extensometers are strain gaged devices, making them compatible with any electronics designed for strain gaged transducers. Most often they are connected to a test machine controller with electronics for a strain channel, and Epsilon will equip the extensometer with a compatible connector wired to plug directly into the controller. For systems lacking the required electronics, Epsilon can provide a variety of solutions for signal conditioning and connection to data acquisition systems or other equipment.

For gauge lengths less than 20 mm (0.8 inches), Epsilon recommends the more compact Model 3442. For gauge lengths 100 mm (4 inches) or greater see Model 3542L.

Download Data Sheet

  • May be left on through specimen failure in most applications.i
  • Full bridge, 350 ohm strain gaged design for compatibility with nearly any test system.
  • All models can measure in both tension and compression and can be used for cyclic testing.
  • Standard quick attach kit allows one hand mounting to specimens.
  • Rugged, dual flexure design for strength and improved performance. Much stronger than single flexure designs, this also allows cyclic testing at higher frequencies.
  • All models have mechanical overtravel stops in both directions. Cable stops are used for overtravel protection where required. Epsilon’s cable stops are fully contained between the arms of the extensometer and do not hang below where they can interfere with fixturing–especially during compression testing.
  • Hardened tool steel knife edges are easily replaced. A spare set comes with every extensometer.
  • Gauge length adapter kits enable configuration of multiple gauge lengths with one extensometer.
  • Replaceable arms and spacers for ease of repair.
  • High and low temperature options extend operation from as low as -270 °C to +200 °C (-454 °F to +400 °F).
  • Includes the Epsilon Shunt Calibration System for on-site electrical calibration.
  • Includes high quality foam lined case.

Download Data Sheet

Excitation: 5 to 10 VDC recommended, 12 VDC or VAC max.

Output: 2 to 4 mV/V, nominal, depending on model

Accuracy: Standard configurations meet ASTM E83 class B-1 accuracy requirements for gauge lengths ≥20 mm and class B-2 for <20 mm. All standard configurations meet ISO 9513 class 0,5. A test certificate is included.

Linearity: ≤0.15% of full scale measuring range

Temperature Range: Standard (-ST) is -40 °C to +100 °C (-40 °F to 210 °F)

Cable: Integral, ultra-flexible cable, 2.5 m (8 ft) standard

Standard Quick Attach Kit:
– Wireforms are included for round samples 2-25 mm (0.08-1.0 inch) diameter and flats up to 12 mm thick by 31 mm wide (0.5 inch by 1.25 inch); wireforms are available for many other specimen sizes – contact Epsilon
– Rubber bands and springs for attachment are also included
Model 3442 is recommended for specimen diameters <2 mm

Operating Force: Depends on model configuration; 10 to 100 g typical



Download Data Sheet

  • Quick attach kit wireforms or cable attachment for large specimens
  • Adapter kits to change gauge lengths
  • Connectors to interface to nearly any brand of test equipment
  • Special coatings and stainless steel knife edges available for biomedical tests 
  • Specialty Knife Edges

Download Data Sheet

Product Videos

Metal tension test with axial extensometer
Quick Attach demonstration

Ordering Information

Get our most popular configurations fast! We ship the following model 3542 configurations in 3-5 business days with a connector for any of the most popular testing machines.

  • 25 mm gauge length, 20%, 50%, or 100% measuring range
  • 50 mm gauge length, 20%, 50%, or 100% measuring range
  • 1 inch gauge length, 20% or 50% measuring range
  • 2 inch gauge length, 20% or 50% measuring range
  • -ST temperature range

Limited to quantity of 2 per order. Customer order must state “Quick to Ship”. Lead time for configurations not listed above is 2-4 weeks.

Quick To Ship Logo

Click table options to configure

Gauge Length i
mm or inches #
10.0 mm -010M¹ 010M
12.0 mm -012M¹ 012M
12.5 mm -0125M¹ 0125M
20.0 mm -020M 020M
25.0 mm -025M 025M
30.0 mm -030M 030M
35.0 mm -035M 035M
40.0 mm -040M 040M
45.0 mm -045M 045M
50.0 mm -050M 050M
75.0 mm -075M 075M
80.0 mm -080M 080M
0.500 in -0050¹ 0050
0.640 in -0064¹ 0064
1.000 in -0100 0100
1.400 in -0140 0140
2.000 in -0200 0200

Measuring Range² i

% strain #
±5% -005³ 005
±10% -010 010
+20%/-10% -020 020
+25%/-10% -025 025
+50%/-10% -050 050
+100%/-10% -100 100
Temperature Range
degrees #
-270 °C to 100 °C (-454 °F to 210 °F) -LT LT
-40 °C to 100 °C (-40 °F to 210 °F) -ST ST
-40 °C to 150 °C (-40 °F to 300 °F) -HT1 HT1
-40 °C to 200 °C (-40 °F to 400 °F) -HT2 HT2
-270 °C to 200 °C (-454 °F to 400 °F) -LHT LHT
Model Number:  3542_ _ _ __ _ __ _
Model Number:
3542_ _ _ __ _ __ _
Model 3542 Available Versions: ANY combination of gauge length, measuring range and temperature range listed above is available, except as noted. Other configurations may be available with special order; please contact Epsilon to discuss your requirements.
¹Epsilon recommends model 3442 for applications with gauge lengths <20 mm (0.8 inches).
²Compressive ranges can be adjusted to higher values if required. Please contact Epsilon for your specific testing requirement.
³Not available in 10 mm, 12.5 mm, or 0.50 inch gauge lengths.

Example: 3542-050M-050-HT2: 50.0 mm gauge length, +50%/-10% measuring range, high temperature option (-40 °C to 200 °C)


If your unit is in need of service, calibration or repair, initiate the RMA process with us and we will be happy to assist.

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Our 2022 Extensometer Catalog, Version 110 is now available! Not finding something you’re looking for? Ask us about a custom quote.