Convenient sizes for plumbing?? electrical?? and door-lock installation tasks</br>Deep-cut style hole saws for improved efficiency and versatility</br>High-speed steel height and double-tooth design for increased durability</br>Hardened backing plates to prevent warping and thread stripping</br>Includes 11 hole saws?? a small quick-change mandrel?? a large quick-change mandrel?? replacement parts?? and case</br></br>Amazon.com</b