The X-iser Mini Stepper is engineered to ensure correct hip and knee alignment,giving you a safe, impact-free workout. The hands-free design promotes the development of your stabilizer muscles and correct posture, greatly improving your balance. The X-iser is the only stepper available with true variable resistance. An adjustable valve enables the user to adapt step intensity in accordance with body weight. The patented interactive variable resistance hydraulic system allows The X-iser Machine™ to respond to any step intensity with the force exerted by the user equaling the force returned by the machine, It is truly an engineering marvel and the best portable mini stepper you can buy.