Why are Nissan Thermoses and travel mugs so popular? It is the Thermos Nissan Difference: Thermos Nissan's exclusive manufacturing process assembles and joins the products in a vacuum chamber, producing a superior vacuum while eliminating valves and fittings that might leak. The result is simple, lightweight, virtually unbreakable, stainless-steel vacuum containers that outperform all their heavier, clumsier counterparts. See the expanded Thermos Nissan line including thermos bottles, travel mugs, coffee presses and thermal cookware.