Barbed Wire, Wire Gauge : 1-5mm

Barbed wire, also known as barb wire, less often bob wire[1][2] or, in the southeastern United States, bobbed wire,[3] is a type of steel fencing wire constructed with sharp edges or points arranged at intervals along the strand(s). It is used to construct inexpensive fences and is used atop walls surrounding secured property. It is also a major feature of the fortifications in trench warfare (as a wire obstacle).