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" 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.