Bought these for my friend's electric scooter. The valve for the front wheel is built in and can hardly be reached with the pump nozzle. The original valve extender was awful with air leaking when attaching/detaching. However, these Milton valve extenders are ideal. They're long enough to give you a good grip when screwing and unscrewing, and best of all, they don't lose air during the process. Absolutely perfect solution for hard-to-reach air valves!