The Klein Tools Conduit-Fitting and Reaming Screwdriver can ream and smooth 1/2'' (13 mm), 3/4'' (19 mm), and 1'' (25 mm) thin-wall conduit. It features a hooded-blade design that keeps the screwdriver tip from slipping out of screws, which is especially handy when tightening hard-to-reach conduit fittings.