Arrow T50 is the most widely used heavy-duty staple platform in North America - replacement ammo for nearly any 3/8"-crown manual, cordless, or electric stapler. This 1/2" leg-length is the bulk 1,250-count box, sized to match the substrate without driving the leg out the back side.

• 1/2" leg length, 3/8" flat crown, .050" (18-gauge) galvanized steel wire
• 1,250 staples per box
• Best use: House wrap, roofing felt and underlayment, insulation batt facing, foam board, plastic sheeting on framing, and heavy upholstery. The standard exterior building-paper leg.
• Fits Arrow T50, T55, JT21, CT50 cordless, ET50 + ETC50 electric, T50AC/T50ACD electric, and most third-party 3/8"-crown manual tackers (Powershot, Craftsman, Ace, Master Mechanic, Stanley, Workpro)
• Arrow MPN 50824 (Arrow encodes leg length in the 3rd-4th digit: 50424=1/4", 50524=5/16", 50624=3/8", 50824=1/2", 50924=9/16"; 50CT24 is the Ceiltile variant at 17/32")
• 0.5583 lb gross box weight

Tip: Match leg length to substrate thickness - the staple should bury its crown without breaking through the back side. As a rule of thumb, leg length should be roughly 2x to 3x the material thickness you are pinning. If the gun jams or the staple bends on impact, drop one leg-size and try again; if the crown sits proud, step up one size.