Imported from SDC, also known as small white cloth, friction white cloth and small white cloth for color fastness. Equipped with ISO standard friction color fastness testing machine (instrument), under the dry / wet conditions required by the standard, set a certain number of back and forth friction times, and then compare the fading (discoloration) and staining grade with ISO standard discoloration gray card & ISO standard discoloration gray card, so as to evaluate its ability to firm the color when the simulated cloth sample contacts other substances. This standard friction cloth is widely used in Japanese standards (JIS), American standards, European standards and Chinese national standards, or in Adidas, Nike and Li Ning standards.