Diablo's Snap-Lock Plus™ adaptor nuts are designed for quick and easy hole saw cup changes for maximum job performance. Diablo's new, high-performance hole saws deliver faster cutting performance and increased productivity thanks to an innovative mandrel design that simplifies the attachment process for fast and efficient hole saw-mounting. Diablo's one-size fits all mandrel system is not just for Diablo hole saws; it will fit other brands of hole saws when using the enclosed adaptor nuts. Easily convert 9/16 to 6 in hole saw cups by threading one of the enclosed adaptor nuts onto your existing hole saw system. Ideal for any corded or cordless drill press or handheld drill.