Reed internal pipe cutters cut pipe from the inside (i.e. drain pipes or sprinkler drops, etc). heat-treated steel, saw-toothed blades on the IC1S, IC1SL, IC3/4S, and IC3/4SL internal pipe cutters make for fast cutting. the IC1A comes with an abrasive blade for areas where the blade may come in contact with concrete or other hard surfaces which would destroy a saw-tooth blade. available in a variety of sizes and styles, all internal pipe cutters fit in a standard 3/8 in drill. during use, flats on the larger cutters keep the cutter from slipping in the jaws of the drill while a lock washer on the smaller cutters keeps the blades from slipping. all saw-toothed internal pipe cutter models cut plastic pipe aggressively and can cut wood for sink lugs. IC1SL and IC3/4SL feature an exclusive, adjustable guide that doubles as a depth gauge. the IC3/4S and IC3/4SL are exclusive in their 3/4 in pipe diameter.