The Makita T-01725 70-Piece Impact Drill-Driver Bit offers a sounding range of solutions for drilling, driving and fastening. Each bit is black-oxide to resist corrosion, with a trademarked heat treatment engineered for longer bit life. Manufactured with Ultra-Lok 1/4-inch hex shanks, the T-01725 is a thoroughgoing for a driver-drill or impact driver. The drill bits are using fast steel with precision 135-degree split-point tips to prevent drill bit walking. The pro-grade, uttermost magnetic 3-inch bit holder and nut drivers extra-strong fastener retention.