Mibro 492470 17-Piece Cobalt Metal Master Set, 1/6-Inch to 3/8-Inches
This 17-Piece Cobalt Metal Master drill bit set from Mibro - a 60 plus year old company selected as one of Canada's "50 Best Managed Companies" contains sizes from 1/6-Inch through 3/8-Inch in 1/6-Inch increments.  Cobalt drill bits are not coated, the cobalt is blended into the high speed steel during the steel manufacturing process to give them their toughness.  These bits can be used use on very hard or abrasive materials such as stainless steel and space age alloys.  They have an extra thick drill core for rigidity and strength.  All the bits have a 135 degree split tip that eliminates the need for a center punch and keeps the drill from "skating."  The sizes 3/16-Inch and larger have 3 flats so the drill chuck can get a better grip, especially helpful on hard materials.  Though cobalt drills are more expensive than high speed steel and titanium coated high speed steel, they will far out last those drill bits making Cobalt bits an excellent value.