For heavy duty stapling jobs such as insulation carpet underlaying and roofing felt. 27/64" Wide Galvanized Steel Heavy Duty Narrow Crown Staples 1/4" (6mm) Leg Length Chisel Point. Fits TR100 TR200 TRE500 series PHT150 PHT250 TR100HL Arrow: T50 T50PBN ETF50 T55 HT50 Powershot 5700 staple guns. This listing is for 5 5000ct boxes (25000 staples). Packaging may vary.