These soft plyometric boxes can be used individually or stacked for variable height options depending on ability and progress. Velcro tabs hold them in place for safety and confidence when stacking, and they’re light weight, so they’re easy to move while in use or for storage. TECH SPEC.The black Plyosoft boxes are made from high-density foam filling with a durable PVC covering. Available in sizes 60cm/24in, 45cm/18in and 30cm/12in. SIMPLE BUT EFFECTIVE.This range is all about no-frills equipment that is tough and effective. Classic design and usability allows users to get back to the fundamentals and concentrate on what matters – performance.