Matco Tools 21 Piece Cobalt Hyper Step Drill Bits Mechanics Length. These are made from Cobalt steel the strongest metal for drill bits. These are more suitable for a drill press for optimized performance but can be used in a power drill. Sizes range from 1/16 to 3/8 if you want to know every size check the pictures. These are brand new never used. Any questions feel free to ask me! This item is in the category "Home & Garden\Tools & Workshop Equipment\Power Tool & Air Tool Accessories\Drill Bits". The seller is "dwil4049" and is located in this country: US. This item can be shipped worldwide.