Two samples are clamped in the folding heads for a simultaneous test. The spring supported sample supports are pulled apart, so that the samples are clamped at the specified force. After pushing the start button, the folding knives begin to guide the sample around the sapphire supported folding rolls. That way, the samples are folded on both sides at a radius of 0.25 mm. If one sample breaks, the folding process of the second sample continues until it breaks too. The movements of the folding knives stop after the test, so that the samples can be removed. The device records and displays the number of folds until the sample breaks.
