Package Includes - Comes with 504pcs sanding bands, 24pcs sanding drum mandrels, 2pcs self-tightening drill chucks and 1pcs combination wrench, 531pcs in total in 1 set Essential accessory for 7 Grits - These sanding bands contain 6 sanding grits (80 grit, 120 grit, 150 grit, 240 grit, 320 grit, 400 grit, 600 grit) and 3 diameters (1/2", 3/8" and 1/4"). Each grit and size has 24 sanding bands for you to use and replace Universal Drum Mandrels - 24pcs reusable drum mandrels contain 3 diameters: 1/2", 3/8" and 1/4", 8pcs for each size. Common and standard size suitable for all rotary tools like Dremel etc. Easy to install - make sure the drum has been screwed in tightly, drum mandrels with self-expanding rubber cushion, which makes the sanding bands close to the mandrel firmly and achieves better finishing; Note: please wear professional safety glasses to protect your eyes as there may be flying grains when the sanding drum rotates at high speed Wide Compatibility - standard and