The set includes: 240 pieces of sanding bands in 3 diameters: 1/2 \", 3/8 \" and 1/4 \", 80 pieces per size, and 12 pieces of sanding mandrels in 3 diameters: 1/2 \", 3/8 \" and 1/4 \", 4 pieces per size; 252 pieces in total. Convenient: Standard size sanding bands and 120 grit, used for smoothing surfaces and curved edges, polishing soft and hard materials, such as DIY, artwork, and woodworking. Easy installation: drum mandrels with self-expanding rubber cushion, which makes the sanding bands fit tightly against the mandrel and provides a better finish; If the sanding band comes loose from the mandrel during use, make sure the drum has been screwed tight and is very close to the sleeve. Note: Wear professional safety glasses to protect your eyes, as there may be lumps when the sanding mandrel rotates at high speed; the sanding mandrel is attracted faster to the metal surface, replace the sleeves in time to achieve the best sanding effect. Bonus: Comes with a free plastic box, convenient to store and search. Quantity delivered: 252 pieces