The package includes - 120 pieces of sanders in 3 diameters: 1/2", 3/8" and 1/4", 40 pieces per size, and 12 piece sanding drum in 3 diameters: 1/2", 3/8" and 1/4", 4 pieces per size; total 132 pieces Must-have accessory - Standard and standard 120 grit size sanding bands used to smooth the surface and curved edges, polishing both soft and hard materials, such as DIY, artwork and woodwork Easy installation - drum chucks with self-expanding rubber cushion, making sanding bands close to the mandrel qualified and obtaining a better finish; In the event that the sanding belt becomes detached from the mandrel during use, please ensure that the drum has been screwed on and is very close to the sleeve Note: Please wear professional safety goggles to protect your eyes, because there may be lump particles when the sanding drum rotates at high speed; the sanding drum will be delivered faster on the metal surface , please replace the sleeves in timely in order to achieve the best sanding effect