Versatile Applications: Our concrete core drill is fabulous for drilling hard concrete, masonry, hard brick, and other hard materials. It is widely used in installing air conditioners, pipes, stair railings, highways, airports, and other conditions. Simple Operation: The core drill can be used to contain your multiple work needs for both dry and wet. Start drilling at the vertical position, then continue to dig deep, and you will get a perfect hole in a second. Humanized Structure: Our diamond dry coring bit features chip removal holes, highly regular sawteeth, and concentric axes design. The innovative construction provides high drilling performance while keeping a long lifetime. Engineered for Exact Fitting: With a 5/8"-11 universal thread, this core drill bit allows easy and rapid assembling to a standard fixed core or handheld drilling machine. It is compatible with most concrete core drill devices. Efficient & Smooth Drilling: This diamond core drill comprises premium aluminum alloy components, and high-quality diamond grits ensure a longer coring life. Diameter: 4.25 in / 108 mm, Drilling Depth: 9.5"/241.3 mm. A pilot bit and an extra 4.5"/114.3 mm blade is included to increase your efficiency.