Want drinkware that stands out from the crowd? Try this fun Polka Dot Mood Mason Jar! The 16 oz. acrylic mug changes color when you add cold liquid. The polka dot pattern starts out clear and fills in with color as the mug gets colder. The lid and straw match the dot color. Add your custom imprint to the front of the mood mug to create a personalized student award, teacher appreciation gift, school fundraiser, and more.