Countersink-Bit-Set-5-Piece-Manufacturers-P-N-12431-Draper-12431-This-set-pilot-drills-and-countersinks-at-the-same-time-producing-a-faster-finish-p-p-Heavy-duty-design-manufactured-from-carbon-steel-C45-p-p-Replaceable-drill-bits-manufactured-from-high-speed-steel-p-p-Drill-bits-can-be-adjusted-and-fastened-with-a-hex-set-screw-p-p-For-countersinking-screw-holes-for-flush-fitting-of-screwheads-in-hardwood-soft-wood-and-plastics-p-p-Fitted-with-quick-change-1-4-hex-p-p