Hummer 2007 H2 Owner's Manual page 467

The accessory inflator hose also has a built-in
air pressure gage. As soon as you start to
inflate an object it will automatically read the
current pressure.
4. Press and release the switch to turn the
accessory inflator on. The indicator light
will remain on while the inflator is running.
When you are finished using the inflator, press and
release the switch to turn it off. Place the inflator kit
tools and the hose back in the pouch.
If your vehicle is equipped with the air suspension
system, load leveling will not function with the
inflator hose attached to the inflator outlet.
CAUTION:
{
Inflating something too much can make it
explode, and you or others could be
injured. Be sure to read the inflator
instructions, and inflate any object only to
its recommended pressure.
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