I'm selling this item because I bought it but haven't used it. I've only tried it out, but it's been stored at home, so I'm hoping someone who understands that will purchase it ^ - ^ [Fully Fabric-Covered, Silent Design] High-density fabric completely blocks the sound of the springs. Allows for training even late at night in apartments. [Lumbar Protection, Flexible Frame] The supple material absorbs impact to the lower back. Prevents injury to internal organs even during long rotations. [High Load with Reinforced Springs] Thick internal springs provide 1.5 times the normal load. Burn more calories in the same amount of time. [Multi-Functional Convertible System] Provides a variety of training options, from yoga warm-ups to fat burning, all in one unit. [Foldable Storage] Can be rolled up and stored in the gap of a bag. Perfect for training in your spare time while traveling or at the office.