Replacement die only, punch and draw stud required for operation | Replacement for punch unit model number 60177 | For use with hydraulic or battery powered drivers | Punch up to 10 gauge mild steel | Align accurately and produce burr-free holesAmazon.ca Product Description Greenlee 60179 4.125-inch (104.8mm) square shaped replacement die to be used with the knockout unit 60177, sold separately, for creating holes in panels. From the Manufacturer Greenlee replacement square die. Full unit includes punch, die, draw stud and nuts. For use with any Greenlee hydraulic driver or battery-powered drivers.