This is the New HSS Steel Large Step Cone Drill Titanium Bit Set Hole Cutter, which is made from high quality HSS steel, and with the Titanium coated to reduce friction and heat. Suitable for cutting holes in a variety of materials including steel, brass, wood, plastic, etc. For Drilling steel, brass, copper, aluminium, wood and plastics , Do not need to use center punch, compared with the ordinary twist drill is not easy to be broken. Size: 4-22 mm（6,8,10,12,14,16,18,20 22）mm , Shank:6 mm (dia),25 mm(L), Total:75mm(L),Allow 1-3mm measurement error. Hex Titanium Step Cone Drill Bit Hole Cutter 4-22MM HSS,. Work while water cooling, can effectively extend the service life of drill bit,recommend drilling rate of 250-250 RPM. 1 x Step Cone Gold Drill Bit
eBay