Add a splash of warmth and color to all kinds of promotional events when you throw these color changing rubber ducks that react to the heat! These 4" x 3.75" x 3" miniatures are made of PVC material with thermochromic properties. Color change occurs when the toy or water temperature reaches 100 degrees Fahrenheit (38 Celsius) and returns to normal when the temperature stabilizes. Choose from a range of base colors -- then add your school, sports team, organizational or company logo or message to customize.