Ergonomic shape designed to minimize hand fatigue. Accepts all popular brands of standard shell holders, including Hornady, RCBS, Redding, and Lee Precision. Plenty of leverage, yet provides needed "feel" for precision primer seating. Integral primer tray and primer punch assembly- no small parts to lose. Comes with large & small size primer tray/primer punch assemblies. Primer tray has a built-in shut-off gate to prevent spilling primers. Primer tray doubles as a flipper to orient primers for use.