When selecting Barbed wire please consider the following:
Barbed wire is basically two strands of galvanised wire loosely twisted together with 4 pointed barbs at approx 100mm (4″) spacing.
Mild steel (MS) is thicker, more pliable and softer. Stretches more when tensioned.
High tensile (HT) is thinner, stiffer and harder to work with or cut. Though it stretches less when tensioned.