Alpha step drill bits are designed for use with thin materials including stainless steel, copper, aluminium, plastics and laminates. The diameters of each step are laser marked for quick reference. Features: Suitable for use with thin materials including stainless steel, copper, aluminium, plastics and laminates Made from high speed steel for an extended product life Titanium nitride coating minimises heat production and improves durability Diameters of the steps are laser marked for quick reference Alpha step drill bits – quick reference Code Size Specs Qty 9STM4-12 4.0 – 12.0mm titanium 1 9STM4-20 4.0 – 20.0mm titanium 1 9STM5-35 5.0 – 35.0mm titanium 1 9STM6-30 6.0 – 30.0mm titanium 1 9STM6-32 6.0 – 32.0mm titanium 1 9STM6-36 6.0 – 36.0mm titanium 1 9STM6-39 6.0 – 39.0mm titanium 1 You can browse the full range of Alpha drill bits here.