Chain tensioner: made of manganese niobium alloy steel, more durable and less damaged than the 45# steel on the market. By "Unwind: patented, more convenient and save your time. Suitable for trucking, ship transportation, air transportation! Tensioners are suitable for transport, handling, shipping or storage." Bale tensioner and fixing function. Different sizes available. Ribbon: made of high strength polyester yarn, standard tension 2:1. width 35MM, 50MM, etc.