Commonly referred to as a combination drill and countersink, this #7 x 3-1/2" OAL 82-Degree Uncoated Solid Carbide Center Drill Bit is used in metalworking to drill and countersink in a single pass. It is also useful for starting hole for a larger-sized drill bit or to make an indentation in the end of a piece in order to mount a lathe center.
