innovative way to warn caffeineaddicts when their coffee too hot to drink, by changing the color of the takeaway cup lid.the product works by warning consumers that their coffee may be too hot by changing from a dark coffee color to a bright red when the lid is applied to a hot drink. as the beverage cools the lid returns to dark brown so you know it&rsquos safe to drink.the smart lid can be used to seal most printed and insulated cups and differentiate takeout venues from those using regular white lids.
