High-speed steel is the material used. This high-speed steel is heat treated in order to increase its hardness, its tensile strength and its cutting life over time. Furthermore, the drill bit's 135-degree tip design not only provides high stability and precision, but also sharpness and non-slip characteristics, which in turn extends its service life. A pre-cut blade cleans the edges of the holes, while a dual rear guide ensures high accuracy. The drill bits are stiff, so they won't bend like long drill bits.In addition to the standard tapered chisel edge, the chip flutes and highly rounded back edge are designed specifically for metal drilling, resulting in precise, clean holes. This drill is extremely durable and adaptable with a tapered handle design that fits well and won't break easily. In addition to improving performance and efficiency, the rotary design increases drilling speeds. Surface treatment prevents rust and wear. When you have a hole of a specific size, this drill reduces thrust force by 50%, ensuring a perfectly round hole. The hex shank reduces rotation in the chuck, and the bit shank is marked for easy size identification.