Drill - SODIAL(R)HSS drill Step drill Tapered Titanium 1/4 Hexagonal Rod For Drilling Screwdriver 4-20mm Material: HSS Surface Treatment: Titanium Plating Length of 4-20 mm drill: about 7.5cm ; 2.95inch step drilling cutting specifications: 4-20mm sizes of drilling in 2mm steps (9 steps)