#77: Cut-Off and Grooving Holders are designed to hold cutting tools such as drills, end mills, reamers, and taps. They are designed with a flat base that allows them to be mounted securely to a machine table, and a central hole that allows the tool to fit snugly into the block In addition, Cut-Off and Grooving Holders are often adjustable, allowing for the tool to be mounted at different angles.CNC: CNC Tool Blocks are versatile and simple way to quickly and easily mount tools with a standard interface on a CNC machine. CNC Tool Blocks are typically made of aluminum or steel and are designed to securely hold CNC Tools, such as drills, end mills, reamers and taps, in place while they are being used. In addition, it can be used to mount tools without having to machine custom tool holders. This makes them a great choice for low-volume production runs or prototyping projects.