Test specimens are easily clamped into one of four sample positions. Three of these positions perform flex testing. The sample is held under a uniform tension of the while moving one end of while moving one end of the sample through a given distance each side of the perpendicular. This action creates flexural stresses and strain on the sample, which simulates normal wear and causes the material to break down. A change in length of the sample gives a further indication of the material's breakdown.