[header] How to store liquor in stainless steel flasks [title] Fill your flask with hard liquor. [step] Flasks are intended for use with straight, undiluted spirits. In general, it is best to fill a stainless steel flask with hard liquors, such as scotch, whiskey, rum, or vodka. 
[substeps] Avoid adding mixers to your alcohol, since many of these contain corrosive or perishable ingredients that can damage your flask. [title] Avoid putting corrosive or easily spoiled liquors in your flask.