12Pcs Titanium Drill Tap Combination Bit Set With Quick Change Adapter, 6Pcs Sae Main Features: 6PCS SAE Thread drill tap set including 6-32NC 8-32NC 10-24NC 10-32NC 12-24NC 1/4-20NC, 6PCS metric thread drill tap set including M3 M4 M5 M6 M8 M10 screw taps, self-centering point, do not need assistant center drilling or center punching, so it has high versatility. Each tap drill is engraved with a label, which is convenient for you to choose the size that suits you. 1/4 inch hex shank fit into most power tools, such as electric drill, bench drill, drill press and tapping machine. 3-in-1 operation provides hole drilling, tapping, deburring and countersinking for a quick and complete job on wood, copper, aluminum, sheet metal and plastic. Made of 4341 High speed steel, the surface is treated with a titanium alloy, which greatly improves the cutting performance of the drill, is more wear-resistant and prolongs the service life. All our products are extensively tested to comply with rigorous and strict QC standards. We offer a 60-day refund guarantee.