The SitSmart Relief relieves lower back pain by improving your posture. The newer SitSmart Pro Gel has a special gel infused memory-foam fill that shapes to your contours and provides additional pressure distribution and maximum comfort. It provides all-day posture support to keep you feeling comfortable for hours. This simple posture corrector works in any type of seat, from office chair to car seats. The patented design cradles the gluteus, providing much needed support. It activates the core muscles by tilting the pelvis and promoting dynamic sitting. Measures 13” x 15.5“. PRO GEL WITH MEMORY FOAM / Gel-infused memory foam. TRACTION / Features anti-slip grip to hold seat in place.