uxcell Machinery Rubber Flexible Bellows Ball Screw Cover 4cm Inner Dia Black Product Name : Ball Screw Cover;Material : Rubber Color : Black;Inner Diameter : 40mm/1.6" OuterDiameter : 60mm/2.4";Size : 4 x 50cm/1.6"x 20"(Inner D* Extension Length) Weight : 129g Package Content : 1 x Ball Screw Cover