Airhead's Designer Series Tube is a new take on the traditional inflatable water tube with an integrated air filled seat / backrest. The 44 inches (111.76 cm) diameter (deflated) Seat Ring is fun and comfortable and designed for use in pools, lakes and rivers. Ring is made from heavy-duty gauge radio frequency (RF) welded vinyl. Ring is lightweight and very portable. Wherever your weekend takes you, don t forget to bring the designer series seat ring by Airhead.