The Bodyglove Sling Duo is a 56in dual boat tube that features Body Glove's Patent Pending S3 Technology TM. S3 Technology TM is designed to give the rider maximum comfort and enjoyment by providing a seating area that is comprised of Neoprene stretched over the opening in the tube. S3 (Suspended Seating System) cradles the towable rider inches above the choppy water, providing a more comfortable ride, no matter what the conditions. In addition, all S3 boat tubes can be used as either traditional sit ins, or as deck tubes as well. The Sling Duo is designed for up to two riders.