10-Piece Carbide Burr Set1/8? Shank: 1/4? By Mastercarver® High-performance tools! Get the high quality carbide burrs you want, at a great price! Genuine carbide burrs are preferred for carving because they outlast standard steel & “high speed steel” burrs. Teeth are mid depth set for quick stock removal & silky smooth finish. Use with flex-shafts, micro & other grinders. Burr specifications: Shank size: 1/8”; Head Diameter: 1/4”; Overall length: 2”. Max. speed 30,000 rpm. Includes plastic storage box.