Sanding disc with valcro backing is made of flannel cloth adhere to the back of abrasive paper or abrasive cloth.It can be punched to circular, triangle,or other special shapes.It is pasted up hard rubber disc pneumatic or electric tool.It is mainly used for polishing auto surface, wood , stone material, metal,  etc... The  waste  scraps  can  go out from the holes,so the workpiece can not be harmed and there is no evironment pollusion.