Thermos Intak Riff Color Changing Hydration Bottle. The Thermos Intak Color Changing Hydration Bottle features unique, trendy, color-changing designs. To activate the color change, just add ice water and these cool designs come to life! The bottle is BPA free, with a single wall stainless steel body and polypropylene top. The wide mouth opening is easy to clean and large enough to fit ice cubes. Perfect for water, sports drinks and other non-carbonated beverages. Not intended for use with hot beverages. 24 ounce capacity, top shelf dishwasher safe or hand wash.