This tester holds both sides of the test specimen and pulls it at a constant speed, to determine the maximum load up to failure and the elongation at failure, and the work required for failure. When a specimen is inserted into this constant-rate-elongation machine, it is secured by two pneumatic clamps, then the test starts automatically. The load cell connected to the fixed side clamp detects load, to calculate, display and outputs on the printer tensile strength, elongation, breaking length, tensile energy, and tensile stiffness.