Material: Made of HSS 4241 Material: Black Chamfer Drill Body Material: #45 Steel Chamfer: 90 Degree Single Chamfer < p>Quality: Heat Treated and Hardened Carbon Steel with Titanium Nitrate Coating for Superior Cutting Performance Use: Use on Steel, Aluminum, Plastic and Wood. The drilling length can be adjusted for different situations simply by loosening and tightening the screw. Dimensions: 3mm (Diameter) x 60mm (L) 4mm (Diameter) x 75mm (L) 5mm (Diameter) x 85mm (L) 6mm (Diameter) x 93mm (L) 7mm (Diameter) x 10mm (L) 8mm (Diameter) x 11mm (L) 10mm (Diameter) x 12mm (L) Features: 1, Made of HSS 4241 drill bit 2, Black chamfer drill body: #45 steel 3, 90 degree single cutting edge chamfer 4, Heat treated and tempered high carbon steel with titanium nitrate coating for superior cutting performance 5, Use on steel, aluminum, plastic and wood. The drilling length can be adjusted to suit different situations by simply loosening and tightening the screw