Thermos 16 Ounce Travel Mug Twin Pack Twin Pack travel mugs have double wall foam insulation that retains hot or cold temperatures. The 16 Oz capacity is great for coffee. The unbreakable stainless steel exterior is easy to clean finger prints and has a easy grip to prevent spills. The Thermos Foam tumblers fit in most automotive cup holders. The sweat proof design will not leave water rings spill resistant slide lock. Hand wash is recommended.Stainless steel exterior with a polypropylene liner