Feature: 1. Scope of Application: Suitable for drilling holes on stainless steel, iron, copper, aluminum, wood, acrylic sheet, etc. 2. Applicable to ordinary pistol drill, electric drill. 3. The drill bit is made of high-quality high-speed steel, high sharpness and wear resistance 4. High drilling efficiency, can be used in industrial and household. 5. Cutting edges are precision ground and processed to ensure fast drilling. Specification: Item Type: Drill Bits Material: High Speed Steel Quantity: 10pcs / box Optional Diameter: 4.0mm, 4.2mm, 4.5mm 4.0mm 10PCS per box / full grinding 4341 (1 box total) 4.2mm 10PCS per box / full grinding 4341 (1 box total) 4.5mm 10PCS per box / full grinding 4341 (1 box total) Scope of Application: For drilling (Suitable for stainless steel, iron, copper, aluminum, wood, acrylic sheet, etc.) Applicable Equipment: Ordinary pistol drill, electric drill.. Package List: 1 Box of Drill Bits