FOMI Thick Premium All Gel Orthopedic Seat Cushion | (16.5" x 18") |ULTIMATE COMFORT AND PRESSURE RELIEF Advanced column buckling technology disperses your body weight evenly, eliminating pressure on the uncomfortable pressure points. This unique gel cooling structure also increases air circulation to keep your bottom cool. RESILIENT The large cushion is 18 x16. 5" and 1. 75" thick. It will maintain its original shape and it won't lose its support, even after long term use. When used for long sitting periods, it will