Features Tungsten steel: made of excellent tungsten steel material, wear resistance, good workmanship quality, high workmanship, reduced labor, no clogging. For engraving: these rotating file bits have fast cutting and high hardness, suitable for engraving wood, aluminium and plastic, efficient and durable. For metal polishing: can be used for notch processing and polishing surfaces of narrow and deep metal materials such as copper, iron, aluminium, alloys, etc. SPECIFICATIONS: Including 5-piece rotary drill bit with 6mm head, 10mm tip outer diameter and 25mm tip length, standard size, easy to install and replace. High hardness: these rotary files made of tungsten steel have a machining hardness of up to HRC70 and can safely and reliably replace the leaf stem wheel for most work. Specification: Item type: rotary drill bit Material: tungsten steel. Usage: suitable for wood carving, root carving, olive seeds, sharp blades Outer diameter of the tip: approx. 10 mm / 0.4 inches. Tip length: approx. 25mm Package list: 5 x rotary drills Package List 5 x Rotary Burr Bits