Jackson Kayaks Happy Thruster
Here's what other sites are saying:
The Happy Thruster is an addition to the Happy Seat, made to use together. The Happy Thuster slides right over the Happy Seat while deflated and stays on while inflated. The purpose of the Happy Thruster is to turn your kayak into a space ship. There is no other system that will give you more lift for huge air than the Happy Thruster. The benefit of this system over the others is that you have a quick adjustment to the amount of volume you add, plus, it is a soft pillow in your spray skirt that protects your face and hands. The Happy Thruster is not made to use by itself.