This oxygen tank holder is easy to install and mounts to the back of your seat * It accepts D and E sized tanks * All you have to do it slide the tank into the holder hand tighten the set screw and you're ready to go * Works with all Golden Tech scooters * Simply select the appropriate scooter type to ensure the correct hardware is recieved * Oxygen Tank Holder for Golden Power Chair: *Fits on the universal mounting bracket on the back of the scooter * Can be used on the Companions Buzzaround Buzzaround Lite and Avenger