Features Durable YG8 Alloy Cutter Head: Experience exceptional wear resistance with our YG8 alloy cutter head, ensuring long-lasting performance for your woodworking projects Versatile Drilling Sizes: Choose from a complete range of 2.8-4mm drilling diameters, making this set perfect for various woodworking and carpentry tasks Advanced Spray Treatment: Benefit from enhanced oxidation resistance due to the advanced spray treatment, which extends the life of each drill bit in any environment Multi-Material Capability: Effortlessly countersink and open holes in wood and aluminum alloy, providing the ultimate flexibility for all your carpentry needs Protective Storage Cases: Keep each drill bit safe and organized with individual cases, ensuring easy access and protection while not in use Features: 1、 YG8 alloy cutter head with good wear resistance. 2、Complete specifications from 2.8-4mm drilling diameter. 3、 spray treatment, and oxidation resistance. 4、For wood, aluminum alloy countersinking, opening. 5、Each drill bit is in their own case for protection. Specification: Item Type:Countersink Drill Bit Material:YG8 Alloy 45# Carbon Steel Type:2.8x8mm 3x8mm 3.2x8mm 3.5x8mm 4x8mm Net Weight: 160 g / 5.64 oz(approx.) Package List: 5 x Countersink Drill Bit 5 x Hex Socket Wrench 5 x Screw Package List 5 x Countersink Drill Bit 5 x Hex Socket Wrench 5 x Screw