UNHO 5pc Titanium Chamfering Countersink Drill Bit Set - 1/4", 3/8", 1/2", 5/8", 3/4"Wood Plastic Metal Rubber Single Flute 82 Degree Drill Bits Titanium coated extends service life up to 6 times that of uncoated products Cut quickly and easily in soft metal, wood, rubber and plastic Ground form special alloy steel with hardened edges for longer service life Size:6mm,10mm,13mm,16mm,19mm Material:Steel