Carbide Burrs: Made of tungsten carbide of extreme hardness, which can be used on much more demanding jobs than high speed steel. Perform better at higher temperatures than HSS. Better choice for long term performance. Double Cut: Combining left and right-hand flutes to produce a chisel-type cutting edge reduces the pulling action, allowing better operator control. More cutting edges will remove material faster and leave a smoother finish than single cut due to producing smaller chips as they cut away the material. Compatibility: Universal size 1/8''(3mm) shank diameter, 1/4''(6mm) bit head diameter. Fits most rotary tools with 1/8" collet such as Air Tools i.e Die Grinders, Pneumatic rotary tools and high speed engravers. Micro Motors, Pendant Drills, Flexible Shafts, and hobby rotary tools. Can be used on a multitude of materials: steel, carbon steel, stainless steel, cast iron, aluminium, titanium, cobalt, nickel, gold, platinum, silver, ceramics, fibreglass, plastic, brass, copper, bronze, zinc, wood Multi-Purpose: Coming in 10 different shapes meets all your needs of finishing, cleaning, smoothing, shaping and carving. Carbide burrs are widely used for metalwork, tool making, model engineering, wood carving, chamferring, deburring, grinding, cylinder head porting and sculpting.