This product is Hi906 PCS 1 Hula Hoop Bodybuilding, a hula hoop that indirectly folds using soft springs. Materials and Structure: The outer layer is made of soft PVC plastic, and alloy springs are used inside. Multi-functionality: It can be used for exercises to train muscles not only in the waist but also in the chest, legs, back, and shoulders (deltoids, trapezius, rhomboids). Convenience: Due to its flexibility, it can be twisted and folded for compact storage and is suitable for carrying. Safety and Quietness: The soft material cushions the impact on the waist, and the design reduces noise during use. 12-672