Large HSS Steel Step Cone Drill Hole Cutter Tools Titanium Bit Set 4-12/20/32mm. HSS titanium coating Suitable for materials with hardness less than 23°, such as aluminum, PV panels, plastic, wood panels, ordinary iron with thickness less than 2mm, etc. Suitable for materials with high hardness, such as aluminum sheet, steel sheet, stainless steel sheet, carbon steel, etc. Multiple applications for a wide range of applications. Automotive sheet metal/repair and modification/bridge doors and windows/household appliances. Sharp and smooth without burrs. 75° spiral angle for smoother chip removal. 118°x-shaped opening reduces drilling slippage. Enhanced chip breaking groove. Effectively blocking the damage caused by splashing metal chips. Clear fiber optic marking. Drill diameter specifications are clearly marked at a glance. Stable hexagonal shank, suitable for hand drill/wind drill and other tools are strong and durable. Based on your choice. Thank you for browsing our products!