The YETI Rambler® Bottle 5 oz Cup Cap turns your Rambler® bottle into a perfectly insulated thermos. This cap not only is compatible with every Rambler® bottle, but also offers twice the functionality. As an insulated cap, it helps keep your coffee, tea, or even whiskey at the perfect temperature, and, when you twist it off, you've got a double-wall, vacuum-insulated cup. Save some space by transforming your Rambler® bottles with the heat-locking, two-in-one companion, the YETI Rambler® Bottle 5 oz Cup Cap!