If you are using a trigger sprayer attached to the non-aerosol Ballistol can, remove after use and return the original cap. Ballistol can leak from the trigger sprayer, and will be exposed to air. Ballistol has an indefinite shelf-life when the original cap is returned to the can. Ballistol will not “mist” out of the trigger sprayer, but will instead shoot a “stream”. For a mist application, please use our aerosol version.