McCarty's Sacro-Ease(R) Ergo Curve is a lumbar-only product and is an economical way to add superior lumbar support to any seat. Simply hand the molded visco-elastic memory foam lumbar unit on your seat with the attached weighted strap and adjust as needed for superior lumbar support. The strap can be moved to use either side of the support as the "top" or "bottom" for maximum flexibility. Includes a convenient carrying handle for portability.