Greenlee 30227 Slug-Splitter Knockout Draw Stud for Ratchet Drivers, 7/16 by 3-5/8-Inch For use with Greenlee ratchet driver 1904 Punch and die are required for operation Slug-Splitter SC heavy-duty punches are designed to punch up through 10 gauge (3.5 mm) stainless steel Self-centering punch aligns itself on pilot hole Unique punch profile also splits slugs for easier slug removal