The Pro-Graad Shaft Adapter is a must-have tool for anyone working with large 1-1/4”-7 threaded diamond hole saws and core drill bits. This versatile adapter allows you to convert your 5/8"-11 threaded power tools to 1-1/4"-7 male threads, making it possible to use 1-1/4”-7 threaded diamond hole saws and core drill bits with standard 5/8"-11 threaded power tools. Constructed from high-quality alloy steel, this adapter is built for durability and reliability, ensuring long-lasting performance even in the most demanding applications. One of its standout features is the built-in water hole at the center of the adapter, which provides efficient cooling for diamond tools during use. This cooling mechanism not only enhances the tool's lifespan but also improves cutting efficiency, making your work more effective and precise. Designed for professional use, the Pro-Graad Shaft Adapter ensures a secure fit and stable operation, whether you're a DIY enthusiast or a seasoned professional. Its solid construction and reliable performance make it an essential addition to your tool kit, allowing you to tackle a wide range of drilling tasks with confidence and ease.