Updated Months Later: I purchased the unit a few months ago after failing to inflate my truck tires at a gas station. A week later I told myself I should have saved my money because it would cost MANY dollars to pay $1.50 for refueling at the airport to fund itself. Currently? WORTH EVERY PENNY! Flat tire on the trailer, filled up in the shed! Low air level in my car filled my parking space. Decorate all truck tires, done! The only thing that could improve the situation would be a longer 12v cable as even with a 12v extension it doesn't reach my trailer's tires but if an outlet is available a standard extension cable will do for me. Otherwise, chances are that when I inflate a trailer tire, it's already off my trailer for me to roll into my truck! ************************* ***** Original review I used this to inflate the tires on my F250 truck and horse trailer yesterday. It won't win a speed contest, but the ability to bolt an air tube to a tire valve means speed isn't critical as you don't have to keep an eye on it. I hooked it up to a low pressure tire of about 15/20 psi and then cleaned my truck's cab. When it turned off I moved on to the next tire and ignited it and then cleaned my truck's body etc. I bought a 12 foot DC extender and without this extender I wouldn't be able to inflate my truck's rear tires. If you want to inflate a trailer tire, you will most likely need a 20 foot extension.