LD-186 HSS Step Drill Bit Cone Cutter 3pc Set | Wholesale Supplier

The LD-186 HSS Step Drill Bit Cone Cutter 3-piece set revolutionizes sheet metal and thin material drilling by replacing entire sets of individual drill bits with a single tool that creates multiple hole diameters. Each step drill features a conical body with precisely machined steps, each step corresponding to a standard hole diameter. As the drill penetrates the material, each successive step enlarges the hole to the next diameter, allowing the operator to stop at any step to achieve the exact hole size needed. The high-speed steel M2 construction maintains cutting edge sharpness through extended use on metal materials, while the titanium nitride gold coating reduces friction, dissipates heat, and extends tool life by up to 3x compared to uncoated bits. A 135-degree split point tip eliminates walking on smooth metal surfaces, enabling precise hole placement without center punching. The 1/4 inch hex shank fits standard quick-change drill chucks, impact drivers, and magnetic bit holders for rapid tool changes on busy job sites. The three-piece set covers the most commonly needed hole size ranges: the 4-12mm bit handles small clearance holes and pilot holes, the 4-20mm bit covers standard fastener and conduit holes, and the 4-32mm bit handles larger knockout and panel openings. Each step is clearly laser-marked with its diameter for easy size identification during use. Whether enlarging holes in electrical panels, cutting openings in HVAC ductwork, drilling body panels in automotive repair, creating holes in plastic enclosures, or fabricating thin metal components, the LD-186 step drill bit set delivers fast, clean, burr-free holes with a single tool.