• Efficient and smooth drilling: this diamond drill bit consists of premium aluminum alloy components and high-quality diamond grains ensure a longer lifespan. • Designed for an exact fit: with a universal 5/8"-11 thread, this drill bit allows for easy and quick assembly. • Humanized structure: our wet diamond drill bit features chip extraction holes and concentric shaft design. • Simple operation: the center drill can be used both dry and wet. • Versatile uses: designed for drilling concrete, red brick, marble, and other materials. • Specification: Model Number: KZ4-9.5, Material: diamond and aluminum alloy, Drill Diameter: 4 in./101 mm, Useful Length: 9.5 in./241 mm, Total Length: 15.7 in./400 mm, Adapter: 5/8in-11, Item Weight: 4.8 kg. • Package Content Included: 1 × diamond drill bit, 1 × blade.