Super Durable Hard Steel - Made of extremely hard stainless steel with high strength and hardness for durability, rust and corrosion. It can be with you for a long time. Safe and Effective - High strength and hardness external deburring tools easily scrape and deburr the outer edges of bolts, pipes or rods, simplifying repairs. Quickly repair damaged bolts and tighten nuts in place without hurting hands, sparks or burns. Simple Operation - A great helper for industry and household. Simplify the repair process to just three steps, reducing repair time and eliminating the need to replace expensive hardware. (Attach the beveling tool to the end of the electric drill. Use the lowest speed on the bit. Press lightly to remove burr.) Wide Application - Bevelling tool is effective on stainless steel, hardened steel, mild steel, copper, brass, aluminum , fibreglass, wood and plastic, with or without screws. Fits Waist (approx.): 5/16-32 bolts (.164) up to 3/4-10 (.750) - (8mm -19mm)