Greenlee round standard replacement metal punches must be used with a matching die and draw stud to operate. They can punch quick clean holes through metal up to 10 gauge (check specs for specific punches). They can be used with battery-powered, hydraulic, ratchet or manual drivers. Properly assembled through pilot holes, they will make clean, fast and accurate holes. After cutting the slug falls free in the die, and a quick tip drops it out.