Similar to an asthma inhaler, the AWOL machines consist of an oxygen generator attached by tubes to a hand-held vaporizer. The user can choose any hard liquor, which is poured into the vaporizer. The oxygen from the generator then passes through a tube and absorbs the alcohol. A mist forms from the two ingredients that the user inhales.
AWOL is a hangover-free way to consume alcohol because of the oxygen in the vapor, which is proven to reduce the feeling of a hangover, according to the product's website. The website also emphasizes that AWOL is safe because both of its components - oxygen and moderate consumption of alcohol - are safe.
The site also markets the product as low-calorie and low-carbohydrate alternative to regular liquor because the inhaled alcohol doesn't go through the stomach.
Inhaled alcohol enters the bloodstream through the lungs instead, and the result is a less-filtered, low-calorie buzz. Regardless, the body expels alcohol the same whether it is inhaled or sipped and can be detected using the same methods so AWOL cannot be used to get around alcohol laws.
Though I've never been drunk in my life, I'd expect just plain Everclear to be as "good." Part of the reason for hangovers is toxic congenerics (other alcohols and aldehydes) that are formed by fermentation, in the beverage. It's the purity that does the trick, not the means of ingestion. As for pure oxygen, how much can there be in those little spritzers?