Hardened, alloy steel straight or tapered Snappy Countersink bits will drill the pilot hole and countersink or counterbore in one operation. The large 1/4" hardened set screw allows you to easily adjust the length of the bit for correct pilot hole depth. The 82 degree countersink angle sets screw heads flush to the surface or, if you prefer, counterbore for using plugs. They have standard 1/4" hex shanks which fit all quick change chucks or standard drills. USA.
Set includes screw sizes; #6 (9/64"), #8 (11/64"), and #10 (13/64").