Glow in the Duck. Angel Duck! Illuminating Bath Duck, water Activated Gift – Child Safe Simply place the Duck on the water and watch the automatic colour changing LED bulbs light up and slowly cycle through colours.Info:The Internal light turns on with contact with water, and off when duck is removed. It takes like a duck to water! The battery lifetime of the Glow-in-the-duck is about 45 hours, the equivalent to 180 fifteen-minute baths! All ducks contain x3 LR44 (AG13) button cell batteries and colour changing LEDs. Batteries are accessible through a small sealed hatch on the bottom of duck. Batteries are replaceable.