SpecificationSelect a model according to the weight and age of the user.Effect:A. Stress killer. B. Time saving. C. Increase enporphins. D. Good for loosing weight. E. Increase HDL-C.Color Available: Black.Where to use: Use it on a broad, flat and strong ground.Avoid using it in places that have plenty of automobile traffic and places that are wet or slippery. In addition, do not use on a bumpy, soft, inclined place.Components: 1) Spring: Special reinforced glass fiber. 2) Body: Aluminum alloy. 3) Step:Rubber. 4) Connection: Bolt or nut. 5) Others: Plastic.Package Included1x Kids/Child Youth Kangaroo Shoes Jumping.