Check the listing for details. 3 Flute 90°HSS Chamfer Countersink Drill Bit Set, 12mm Shank, 30mm & 40mm Length. Color: Silver, Condition: New. Listed at 18.99 USD. Product name: 90 degrees straight shank chamferer Product features. 1.Made of high quality high speed steel, quenching treatment, long service life. 2.Three edges design, cutting at the same time, high efficiency of chamfering. Applicable machine tools: Bench drills, milling machines, etc. Shank: Round shank Applicable materials: iron, stainless steel, copper, aluminium, etc. Chamfering work on various metal materials (HRC 25° or less Material Die steel 304 stainless steel Copper) Caution: 1.drill holes before chamfering. Cannot be used directly for chamfering. 2.Please ensure concentricity when chamfering to avoid uneven edges. Material: 6542 HSS 001: Shank diameter: 12mm Cutting diameter 40mm 002: Shank diameter: 12mm Cutting diameter 30mm.