What is a 12 volt air inflator & what would it be used for?
Make sure and do your homework for a 12 Volt Inflator. The ones that plug into a cig lighter socket are marginal at best. Some may take 10-20 minutes to inflate a tire.
Look for one that will use clips like jumper cables to attach to the battery.
The superflow is one that comes to mind. I have used it to inflate a tractor tire. It will inflate a large pickup tire in a few minutes.
http://youtu.be/qkkB0XOuB8k