Osaki OS-Pro Omni is an innovative full body L-Track massage chair with 2 stage zero gravity and unique foot roller. As the roller system massages the neck area， it continues through to the lower back and then proceeds to massage the glutes and upper hamstrings. When activating the chair， it will initiate an auto body scan measuring the key areas of the back including the height of the user. This allows for the chair to deliver a highly effective massage with consistent pressure throughout the course of the pre-set program. Before the body scan starts it is recommended that you comfortably position yourself where your back is completely pressed against the backrest for an accurate reading. Inspired by NASA technology， the Zero Gravity position is the perfect position to enjoy a massage， aligning your back relative to your thigh at an optimal level of comfort. When reclined into the zero gravity position， the complete weight of your back is virtually supported by the backrest which maximizes the intensity of the massage. There are 2 stages of zero gravity.