This back perch provides contoured back support, which helps properly position lower back, thereby promoting good posture and minimizing strain and fatigue. Base is made of durable recycled foam material (100% reclaimed foam). The cover is made of 89% post-consumer recycled Polartec ™ fleece, which is removable and washable. Cover has straps that secure backrest to virtually any chair. Blue. 13" W x 13" D x 2 ½" H.