General description Multi-tooth TCT tip thick heavy-duty carbide alloy drill bits designed for high hardness, rust-proof, sturdy, and durable performance. This set includes 6 pieces of high-quality carbide drill bits with diameters ranging from 22mm to 65mm, capable of cutting through various materials including steel, stainless steel, copper, brass, fiberglass, iron, aluminum, wood, and different types of pipes. Technical specifications Material: Carbide and Alloy Steel Boring Diameter: 22mm/0.86", 30mm/1.18", 35mm/1.38", 45mm/1.77", 50mm/1.97", 65mm/2.56" Total Length: Approx. 68mm / 2.68" Shank Diameter: Approx. 9mm / 0.35" Installation Should be installed for use in an electric drill. Can also be fixed on hand drills and augers. Usage Widely used for drilling holes in stainless steel plates up to 3mm thick, iron plates less than 10mm, and for hole operations in aluminum alloy metal. Ideal for installing locks and knobs in doors and cabinets, or drilling larger diameter holes