Description: These bits work fantastic on PCB boards. Sharp and twisted flute will make the drilling be more easy and effortless. They come in a easy-to-use plastic case with a holder for each bit. Drills bits are perfect for delicate drilling through hard materials for model engineering, jewelry repairs, craft work, s uitable for PCB, SMT, CNC, mold, sculpture, plastic, copper, stainless steel. Features: Use high quality materials and fine grinding process makes bit more sharp cutting edge. Drill bit has a large scraps discharge space, little resistance and smoothly during the scraps discharge. Reduce cutting force and broken drill, improve the quality of hole wall. Easy to change out and do a great job cutting through the PCB for solder holes. Come in a great storage container that is easy to find and grab the drill bit you need when you need it. Specifications: Material: Cemented carbide, HHS Ring Color: Mixed random colors Cutting Edge Diameter: 2.1, 2.2, 2.3, 2.4, 2.5, 2.6, 2.7, 2.8, 2.9, 3.0mm Shank Diameter: Approx 3.175mm Length: 38.1mm / 1.5" Quantity: 10pcs Weight: 45g(approx.) Package Includes: 1 Set(10pcs) x Drill Bits Note: Due to different batches, color of rings might be different from the ones in picture. Please take the real one as standard. Thanks for your understanding.