Flexible 15.7 Inch Track for Full Back Coverage - The SKG TS700 4D Shiatsu Back Massager has a 40cm flexible track that glides seamlessly from your lower back to upper spine, providing wider coverage compared to other back massagers. Choose from Full Back, Upper Back, or Lower Back modes for a personalized massage experience. High-Torque Copper Motor for Quiet, Powerful Performance - Equipped with a durable copper motor, this back massager offers high-torque performance, capable of handling up to 220lbs lean in force without stalling. With three heat levels (113℉–131℉) and a rapid 3-second heat-up time, it provides deep muscle relaxation and effective relief exactly where you need it. Ergonomic Dual-Layer Design for Comfort and Support - This back massager has an ergonomic dual-layer sponge system that strikes the balance between softness and firm support. Its wraparound design comfortably supports your lower back, and it can double as a lumbar pillow when not in massage mode. Ultra-Slim and Portable for Easy Use Anywhere - At just 1.57 inches thick, this ultra-slim back massager is compact and easy to store. Whether you're using it on a chair, sofa, or in your car, it's for on-the-go relief. With a long-lasting 3200mAh battery, enjoy up to 90 minutes of cordless use, and the washable cover makes it easy to maintain.