Constructed from moulded polyurethane foam. Contoured profile provides ultimate comfort and relief. Provides relief to endangered areas when sitting for longer periods. Lightweight and easy to transport. Fitted cotton inner cover (outer covers available). Size: 44cm (17½”) diameter x 8cm (3″) deep. If this product is showing as out of stock (red dot), please note that as we manufacture this product on site it can normally be manufactured and available within 2/3 days of receiving your order.