The ST400 barbed fence staples are 4mm (9 gauge) in diameter and are recommended for rural livestock fencing, medium mesh, heavy mesh and heavy woven fencing. It is also great for highway boundary fencing. The staples have also been used in rural utility applications to attach earth wires to power poles.
Available in:
2” (50mm) length barbed staples - A12635
1 3/4” (45mm)  length barbed staples - A12625
1 1/2” (40mm) length barbed staples - A12615