About This Titanium Coating: Classic HSS 4241 construction with titanium coating for capability and durability. The cutting edge is hardened and honed for sharpness and features a chatter-free design with staggered cutting teeth to ensure precise countersinking and clean, smooth holes Quick Change: 1/4-inch hex shank fits into all 1/4" hex shank power drills easily and securely and made for locking into a quick-change chuck Organized Holder: Each bit has an assigned hole in a drill bit holder with size indexing for easy storage and quick organization Includes Size: 30 Sizes: 1/16, 5/64", 3/32", 7/64", 1/8", 9/64", 5/32", 11/64", 3/16", 13/64", 7/32", 15/64", 1/4", 17/64", 9/32", 19/64", 5/16", 21/64", 11/32", 23/64", 3/8", 25/64", 13/32", 27/64", 7/16", 29/64", 15/32", 31/64", 1/2" Fast and Efficient: Suitable for wood, carbon steel, sheet steel, fiberboard, rubber, plywood, PVC, plastic etc Overview Material : High Speed Steel (HSS) Cutting Diameter : 0.06 Inches Finish Type : Titanium Shank Type : Hex Cutting Angle String : 135 Degrees