Sea to Summit X-Mug Cool Grip campingmug. This collapsible mug from the innovative X-Series is useful for anyone who travels and is looking for a mug that can be easily stored. The X-Mug features a silicone base and rim for comfortable drinking and a durable, collapsible body. It holds 480ml and is ideal for hot or cold beverages. The Cool Grip feature ensures a comfortable hold even with hot liquids. Perfect for camping, hiking, or everyday use.