Use screw pilots for drilling clean pilot holes in wood, plastic and composite materials. Screw pilots provide fast countersinking and counter boring in one operation. Fits all cordless screwdrivers and drills, variable speed drills and screw gunsFast countersinking and counter boring in one operationDrills clean pilot holes in wood, plastic and composition boardReplaceable drill bit 3/32 in., 7/64 in., 1/8 in. and 9/64 in.1/4 in. hex shank4 piece set for No. 6, No. 8, No. 10 and no. 12 wood screws