Extra-Large TravelMate Seat Cushion with Specially Designed Non-Slip Cover to Prevent it from Sliding Even on Polished Marble Floor (Size: 19 x 17 x 3 inches) Every product comes with the trademark TravelMate Extra-Large size: 19 x 17 x 3 inches. The combination of a layer of high density memory foam on top of a furniture-graded foam provides enhanced comfort and durability. Note: Cushion needs time (one week of usage is typical) to break-in. Dissipates pressure effectively while conforming to body contours. This newly released and improved version includes a high quality cover coated with a non-slip silicone layer at the bottom of the cushion to prevent it from sliding even on polished marble floors. Color: Grey