10 piece Durable Collet Nut Set #4485 Compatible for Dremel and other Rotary tools. Will Compatible for Dremel except discontinued Models 1, 2, and Series 1 or earlier of discontinued Models 260, 270 and 280. It also fits many other compatible rotary tools. Collets nuts are Compatible for Dremel 225 and compatible Flex-Shaft attachment. BRAND NEW and made of high quality material for reliable performance. Durable and long-lasting for extended use.