Rotary burr, tapered head, single cut, 25 mm long, 13 mm thick, alloy steel. Designed for professionals and DIY enthusiasts. Includes 6 common shapes: curved cylinder, round shank, concave arc with ball point, cone, cylinder, inverted cone. The double cavity is ideal for low-density materials. Universal size: 6 mm shank, compatible with all cordless drills, electric drills, air tools, die grinders and other rotary tools. Durable and reliable: Machines up to a hardness of HRA85 and replaces small grinding wheels for most dust-free work. Machining all types of metals (including all types of hardened steel) and non-metallic materials (marble, bone, jade, etc.). Can be used on drills, lathes, portable or flexible electric or pneumatic tools. Can replace small grinding wheels for most dust-free work. Safe and reliable, it reduces labor intensity. Contents: 1 set of rotary grinding heads. (Other products are not included.) WARNING 1) The measurements are taken at Hand measurement, 1-3cm