... :39.1mm,61.8mm,101mm, 35mm,50mm,70mm,100mm 1.triaxial membrane 2.rubber membrane Diameter:39.1mm,61.8mm,101mm ... rubber membrane for triaxial test.such as:Diameter:39.1mm,61.8mm,101mm,35mm,50mm,70mm,100mm rubber membrane for triaxial testing equipments