HJL,
I’ve discovered that bicycle inner tube encased Zippo lighters fit nicely inside a used Tic-Tac plastic case with a little extra space for some tinder, spare wicks, and flints inside the lid. I store my extra flints inside coffee stir stick segments. The Tic-Tac case protects the lighter and provides an extra barrier to slow down the evaporation process. I’ve also used Naphtha in my Zippo while deployed. – RLH in Ohio