【Cost-effective combination】: A combination of 11 commonly used sizes of annular cutters with a 1-inch cutting depth(7/16", 1/2", 9/16", 5/8", 11/16", 3/4", 13/16", 7/8", 15/16", 1", 1-1/16"). It also includes 1 piece of 1/4” hex wrench and 2 pieces of 6.35mm x 77mm pilot pins. 【M2 HSS】: M2 high-speed steel has excellent hardness (usually 62 - 65 HRC), toughness and wear resistance after heat treatment.(2-3x Longer Life than normal HSS Drill Bits) 【Weldon Shank】: The design of the Weldon Shank effectively reduces vibration and deviation of the sheet metal drill during high-speed rotational cutting, ensuring machining precision. It is easy to install and compatible with most brands of magnetic drill machines on the market, such as Alfra, BDS, Dewalt, Hougen, VEVOR, S&F. 【Multiple Application Scenarios】: The annular cutter set is suitable for various metals, such as Steel, Aluminum, Copper, etc. It is widely used in industrial fields, including machining, repair, mold manufacturing, etc. 【Safety Precaution】: Always wear appropriate personal protective equipment (PPE), including safety glasses, gloves, and protective clothing. Do not attempt to touch or adjust the cutter while it is in operation. Keep hands and other body parts away from the working tool. This Annular Cutter Set includes 11pcs annular cutters (7/16", 1/2", 9/16", 5/8", 11/16", 3/4", 13/16", 7/8", 15/16", 1", 1-1/16"), 1pcs 1/4”hex wrench, 2pcs 6.35mmx77mm pilot pins. 1 inch cutting depth for each drill cutter. Every annular cutter with a 3/4-inch Weldon shank (with 2 flats), which can be adapted to all magnetic drill presses, and enables firm clamping and edge finishing. It is designed to smooth the edges of drilled holes, ream holes and remove burrs. Optimal results can be achieved by applying stable pressure during the cutting process.