The 31" Adjustable Aerobic Step Platform is revolutionary. This essential addition to any fitness regimen is one of the best ways to up your cardio with an intense aerobic session, strengthen key leg muscles like the hamstrings and glutes, and target back, arms and chest – all without switching equipment. The aerobic Step platform (30.7 X 11.4 X 4 inches) is easy to store without taking up much space. Adjustable risers lock in under the platform, allowing you to start with an easy workout and up the intensity by raising the 4" platform to 6" or even 8". This platform provides everything you’re looking for – portability, ample workout options and essential safety features. The Platform can support over 400 pounds and has a safe shock absorbing, nonslip surface. This product is backed by a 90-day manufacturer's warranty period.