Color changing Cups : Just add cold water or your favorite iced drinking in these plastic cold tumblers,you will see funny color-changing in these cold cups.
When the temperature is low and below 59°F, the cup itself will also change color;
These 710ml cold tumblers cups, lids and straws are made of BPA-free food-safe grade materials, the splash-proof design lids help to reduce spills and messes, please cover cups lids with a little strength for spill-proof; 
These reusable cups with lids and straws, the tumblers and lids are stackable and save space, so that they are perfect for your holiday travel, party, bring them along wherever you go.