HSS Step Drill Bit - - Our step drill bit is mainly for drilling processing of wood and steel, including metals, aluminum, wood, plastics, etc. Superior Material - - Titanium coating 4241 (HSS) high speed steel reduces friction. They are more durable than uncoated drill bits and HSS (high speed steel) has a long service life Multi-Purpose - - According to the need to process different diameter holes, no need to replace the drill bit and hole positioning, double cutting blade design to cut faster, automatic deburring of the hole when drilling Application - - 4mm precision holes can be drilled into 32mm holes of different sizes Suitable For - - Drilling tools, bench drill. Working in water cooling, can effectively extend the life of the drill bit Product Description Feature - This drill bit is made of high quality HSS steel and with titanium coated to reduce friction and heat. - Suitable to use for drilling holes in a variety of materials, including steel, brass, wood, plastic, etc. - No pilot holes or pre-drilling required and automatically deburrs holes as you drill. 2 fluted edges for faster, smoother cutting. - According to the need to process different diameter holes, you can achieve the point processing of large holes, no need to replace the drill bit and hole positioning. - The use of tools: drill, bench drill. Working in water cooling, can effectively extend the life of the drill bit. Specification - Material: made of high speed steel 4241 - Handle: 10mm triangle round handle - Surface treatment: nitrogen treatment - Spiral groove drilling scale 4-32mm - Scale: 4,6,8,10,12,14,16,18,20,22,24,26,28,30,32mm