Designed to Keep Kids in the Tub and Help with Sensory Development Glo Pals are liquid-activated, meaning they only work when water is in the bath tub or in a container. Draw a bath or fill a container with water, drop the Pals in, and watch them light up! Each Pal has a face and a different personality, and when placed in liquid, the faces will project onto their surroundings, making for fun interactions! Water Activated Glo Pals only glow when they are in the water. The moment you take them out they automatically shut off. It's the perfect bathtub aid to keep your little one in the water long enough to get clean. Sensory Development Glo Pals will teach your little ones about cause and affect, colors, shapes, and light play. Just put them into a container or jar with water and watch them play and learn. LED Lights Each Glo Pal contains a bright LED light that shuts on and off automatically. The lights last 8-9 hours total. Only the time that the product is lighted will count against the battery life. On average, a Glo Pal should last for a few weeks.