The polytex belt from Bach is a versatile tension belts. The strap has a ladder buckle sewn into one end. If you thread the strap through here, you can tighten the strap, but also easily loosen it again. The high-quality belt strap is largely UV-resistant and has a good, robust grip. Cheap belt straps, especially polypropylene straps, are usually too soft, run poorly in the buckles and are stiff as a board after a few years. The polytex strap holds when it needs to and is still light to adjust.