The webbing core is woven in Leeds and has a breaking strain of 440 KG. Stitching has been reinforced at all stress points. The metal buckle has been tested for strength and durability. Please note: it is heavier than a plastic buckle. Breaking load: 20mm, 160 kg; 25mm, 200 kg. Made of zinc diecast with stainless steel pins and springs. Operates without freezing in sub-zero temperatures.