2009 LE Replacement Tires

[chuck jones]

Here's a little extract from Wikipedia to assist you in finding a "local source", which njjoe so adroitly discovered. Unless I'm wrong, it should be readily available at the end of a compressor hose. But check your local atmospheric conditions for variances:

Composition of the Atmosphere
Composition of Earth's atmosphere
The atmosphere is primarily composed of Nitrogen (N2, 78%), Oxygen (O2, 21%), and Argon (Ar, 1%). A myriad of other very influential components are also present which include the water (H2O, 0 - 7%), "greenhouse" gases or Ozone (O, 0 - 0.01%), and Carbon Dioxide (CO2, 0.01-0.1%).