WOW World of Watersports, 15-2060, Aqua Treadmill 1 to 4 Person, Human Powered Floating Vehicle, Steerable Inflatable human powered vehicle for 1 to 4 people Sprockets turn this inflatable water tube into a human powered vehicle that enables you to move across the water at speeds up to 10 mph See through construction so you can see where you are going 60" high center cockpit, be seen on the water 8 drainage ports, grommet with 10 foot rope for tying off