My husband needed this kit to install a new faucet in our basement bathroom. He had to cut a 1-3/8 inch hole in the sink because the hole was too small for the new faucet. He adjusted the saw to a smaller mandrel and it worked great. There were no instructions so he had to find out. "How to install a saw. He used a cordless drill and the mandrel just fit in the chuck. In fact he had two cordless drills and only one of them fit. The set comes in a nice lockable case that everything included He is a former machine shop owner and still loves to tinker and use his own tools.