Shop-Tek 80598 4pc Countersink, Titanium Coated, #6, 8, 10 & 12 Four piece set includes bits for drilling pilot holes for screw sizes #6, #8, #10, and #12 Special designed steel counter sleeve countersinks or counterbores pilot hole Adjustable counter sleeve depth with allen wrench Standard 1/4-Inch hex shank is quick change compatible TiN coated brad point pilot drill bits (#6 bit is not brad point)