This step drill bit set features a jam-free design and dual-flute structure. Compared with similar products, it doubles the drilling speed, significantly saving operation time and improving work efficiency. With a service life extended fourfold and the capacity to complete 50% more holes per battery charge, it reduces the hassle of frequent bit replacements and recharging. Crafted from high-speed steel and black oxide M2 material, the drill bits combine high strength and wear resistance, making them suitable for various materials such as metal, stainless steel, and plastic. The tapered design ensures accurate drilling every time, while the 1/4-inch impact shank provides a secure connection to power tools.The unique stepped design allows the bits to function as either a single drill or a step-down drill, meeting diverse drilling requirements. The spiral flute design with different steps enables smooth and efficient drilling through materials of varying thicknesses without the need to frequently change bits.