About this item These 24-oz cold tumblers cups, lids and straws are made of high-quality food-graded materials, BPA-free and easy to clean, even if put these reusable cups in the dishwasher is safe. Please cover lid with a little strength for splash-proof. When you add your favorite cold drinks and ice cubes in these plastic cold tumblers, a magic color-changing will happen to these cold cups. TIPS: Pour ice cubes and drinks in the cups at normal temperature and it will change color, the temperature under 59F will change the cup's color as well. Bulk tumblers and color changing cups with lips and straws, the best gift for your children, families and friends, perfect for your party, too. Obviously color-coding is a great way to stop someone stealing your drink, and a must-have for allergy sufferers Diy your tumblers: Colored cups, lids and straws allows you freely combining them depend on what you like, and you can adhere your favorite adhesive vinyl works on these reusable color changing tumblers, nice gift for children's operation ability, colors-changing will draw their eyes. These tumblers with lips and straws, the cups and lids are stackable to save space, so that they are convenient to carry everywhere when you go out to play.