Features Aluminium Chromium Nitride (AlCrN) coating, offering up to 10x more life than a standard Milwaukee step drill. Rapid Strike tip allows accurate start without walking and fast drilling without the need to pre-drill the material, and the tip and step geometry reduces the risk of the drill snagging when used with cordless tools, also preventing deformation of the drilled material. Optimised 2-flute, ground sharpened edge geometry provides fast and smooth cutting. Secure 3-flat grip prevents step drill from slipping in the chuck and ensures maximum transmission of torque. Also features laser-engraved size markings for best long term visibility. For steel and stainless steel. Steel 10mm Triangle Shank 4mm - 20mm Suitable for Stainless Steel, Steel, Cast Iron, Wood & Aluminium Alloy Steel Self-Centering Tip Steel 10mm Triangle Shank 4mm - 20mm Suitable for Stainless Steel, Steel, Cast Iron, Wood & Aluminium Alloy Steel Self-Centering Tip