Fabric Automatic Stiffness Tester ISO9073-7/ ASTM D1388-1996/ BSEN22313 SL-F37 Fabric Automatic Stiffness Tester Product Information The bending properties of the fabric are important physical parameters for studying the properties of the fabric such as stiffness, drapability and softness. The instrument uses two mechanical indexes of bending length (also known as drape stiffness) and bending stiffness (also known as bending stiffness) to express "the ability of the fabric to