When sourcing luxury massage chairs, the 3D or 4D massage mechanism is the most critical component. Unlike standard 2D rollers, 4D mechanisms allow for speed and depth adjustments, mimicking the touch of a human therapist. Ensure the product features an SL-Track design, which extends the massage range from the neck down to the hamstrings, following the natural curvature of the spine. Additionally, verify the inclusion of AI body scanning technology to ensure the rollers automatically calibrate to the user's height and shoulder width.