Craft Pro-Quick-Release-Drill-Bit-Guide-Set-3-Piece-Trend-CR-QR-DBG-SET-p-The-Trend-Craft Pro-Quick-Release-Drill-Bit-Guide-Set-provides-accurate-self-centred-pilot-hole-drilling-for-hinges-&-lock-face-plates-High-Speed-Steel-HSS-drill-bit-for-long-life-sprung-loaded-to-ensure-it-retracts-safely-Easily-dismantled-for-cleaning-&-drill-bit-replacement-p-p-Suitable-for-use-on-timbers-&-boards-Use-in-quick-chucks-&-impact-drivers-p-p-Shank-1-4in-Hex-br-Size-to-Screw-S