Taper-Lok Drills and Reamers also known as Taper-Lock Cutters, are manufactured to the most stringent tolerances for precision hole preparation. Standard in HSS or M7 high speed steel, they are also available in cobalt and carbide. A complete line of Taper-Lok gauging tools is also available.Spiral Flute, Taper-Lok Cutters (also known as Taper Locks&amp) Drill, Ream and Countersink in a single operation. The AR series produce a Countersink hole. Taper-Lok Drills and Reamers are manufactured to the most stringent tolerances for precision hole preparation.