The X-Mug is a collapsible mug that is also calibrated as a measuring cup. The flexible silicone sides collapse making this a small compact disc sized dinnerware piece that nests neatly with other X-Series dinnerware and X-Pots. Enjoy your favorite campsite beverages while saving room in your pack with the collapsible Sea To Summit X-Mug. Volume is 2 cups (480 ml). Flexible food grade silicone side walls that can withstand temperatures up to 300°F. Collapses flat for compact packing. Calibrated ridges act as a measuring cup. Spill-resistant and easy to pour from. BPA free