Crown Sporting Goods 18" Round Heavy Canvas Zafu Meditation Cushion (Black) Dense, 100% cotton fill provides proper amount of elevation and firmness, but is soft enough for comfort and movement Creates deeper states of meditation by relieving hip, knee, and ankle joint stress, bone pressure, and by encouraging proper spine alignment Durable and resilient heavy canvas cover withstands daily use and is easy to care for: simply unzips and removes for quick washes 18" diameter and a substantial, cozy 6" thickness Features a handy carry strap and low-profile, reversed zipper