Right for the job:This copper pipe cleaner kit prepares copper pipes, tubes, and fittings for soldering / sweating. Internal locking mechanism for the pipe cleaner:The newly-engineered internal locking mechanism in the pipe cleaner improves the durabilityand reduces the likelihood of shank relative to housing. Standard size:They work for standard copper, bronze, and brass pipes and fittings. is the nominal size for the standard pipes, but the measured OD of pipes and ID Used on power drills:The hex shank is compatible with most power drills. The brushes are used at low speeds on power drills (not impact drivers),and are run in clockwise direction (not designed for counterclockwise direction). It makes the cleaning job much easier and faster. Tools for everyone:It is a tool set for homeowners, DIYers, plumbers, and contractors etc.