A technology that suspends one container inside another, leaving a small amount of air between the two to insulate the inner contents from external temperature changes. (Shorter: Your coffee stays hot.) A modern thermos can keep cocoa steaming for hours in the backcountry. More important, the emergence of double-vacuum steins have doomed the beer koozie to irrelevance.
Vacuum, Double

(Photo: Tim Tomkinson)
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From ϳԹ Magazine, August 2015
Lead Photo: Tim Tomkinson