HSS Step Drill Bit - - Our step drill bit is mainly for wood and steel drilling processing, including metals, aluminum, wood, plastics, etc Material Superior - - Titanium coated 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 cutter blade design for cutting faster, the hole automatically deburring when drilling Application - - 4mm precision holes can be drilled holes of 32 mm in various sizes Suitable For - - Drilling tools, bench drill. Working by water cooling, can effectively extend the service life of the drill bit Feature - This drill bit is made from HSS steel high quality 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 spot processing of large holes, no need to replace the drill bit and positioning of the hole. - The use of tools: drilling, bench drill. Working by water cooling, can effectively prolong the service life of the drill bit. Specification - Material: made of 4241 high speed steel - Handle: triangle round handle 10mm - 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