We take pride in our air quality. Our air is tested by Trace Analytics several times during the summer to ensure your breathing the best air possible.GET FREE AIR! Free fills for the year when we Visually Inspect your cylinders! $30 charge for all visuals!Nitrox not included!Nitrox mixes to your request and all MOD's figured at 1.6!4500 PSI fills available!All cylinders MUST have a current Visual Inspection sticker WITH a shop or training agency affiliation! NO generic (I bought this off the internet) stickers!