Multi-grain sanding discs ----- 100 pieces per box, 5 different sets of sandpaper with sandpaper till fine, 20 sanding discs 40/60/80/120/180 with Velcro to give you more options if needed. 125mm diameter 8 hole mixed grain ideal for all 5 inch grinders. High Quality ----- High quality aluminum oxide grinding wheel holders made from aluminum oxide abrasives with special heat treatment have excellent resistance to polishing, sharpness and wear and tear. Durable and anti-static, great choice for sanding and polishing. 8 holes are designed for efficient dust extraction. Easy to use ----- Velcro closure, easy and quick to stick, strong and durable, will not fall off when installed, easy to install and remove. Widely Used ----- Mainly used in grinding, polishing, etc. wood, plastic, stone, glass and other materials, metallic and non-metallic materials with various intricate profiles to remove rust, peeling paint, deburring and grinding of weld spots. Even the sand ----- resin bonding