This full-length back support cushion feature 10 zones for proper alignment and ergonomic support in any chair or auto. The unique shape is so effective because it was inspired by the body's natural posture and designed to fit the curves of your back. It helps support your low back, lumbar area, even helps position legs and tail bone area. The spinal groove keeps provides a place for your spine to comfortably rest while the full-size back support from your shoulder blades down to your tail bone. Lightweight and portable design.