Arrow ARRT50PBN T50PBN Staple Nail Gun The Arrow T50PBN Professional heavy-duty tacker gun has an all steel construction with hardened steel working parts and jam resistant mechanism. It has an easy squeeze double leverage operation, a visual staple refill window and over 50 years of tested durability. It has a Hi-Viz cushioned non-slip grip. Fires: T50® staples: 6mm (1/4 in) to 14mm (9/16 in). 18 gauge Brad Nails up to 15mm (5/8in).