Designed for various body types, the massager intelligently detects shoulder position, adjusts massage location and back width to perfectly conform to body curves, ensuring accurate massage 50 Inch SL Track Massage: The massage chair features a 50" SL track, stretching from head to legs, for a perfect body fit. It also allows you to adjust massage speed, width, and recline angle to customize relaxation 3 Levels zero gravity: Zero gravity massage chair can be adjusted by 3 levels. Resulting in a total angle of 160°when fully opened. It simulates the state of weightlessness in space, so it can reduce the pressure on the spine and heart, and promotes blood circulation