The Bostitch bta704-5 1/4" Staples Heavy Duty 5,000 sets are designed for domestic use projects, with heavy duty stapling jobs such as insulation and carpet laying and roofing felt. The colour packaging makes it easier to size and choose the products. These heavy duty steel staples at 10/64" narrow spine width - fits Stanley TR110, TR150, TR150HL, TR250, TRE550, TRE650 series, PHT150 pht250 PHT350 and arrow; t-50.