aluminum oxide hook and loop fastener back sandpaper specification : 1)Abrasive: Aluminum oxide, silicon carbide,zirconia oxide 2)Grit size: 40#--1500# 3) Size: the diameter and holes can be ordered 4'',4.5” 5'',6'',7'' ,9"etc 4) Types: adhesive disc and hook and loop fastener disc (non-porous and holes) 5) Remark: Different sizes of hook and loop fastener Sanding Pad can be available,we manufacture according to clients requests. Application: -- Suitable for hook & loop salver and self-adhesive pad used for precision polish of inner hole and flex tube -- Ideal for polishing and grinding the automobile surface coating, woodwork lacquer, painting, carpentry, marble, metal and mold, musical instrument, glass, ceramics Notes: Ideal storage conditions: -- Temperature: 15 - 25C -- Relative humidity: 50 - 65% -- Keep away from heat -- Avoid direct contact with the floor