Blink Ball extends your playing time into the evening & night time. Perfect for the beach or park, especially after dark. It's a whole new ball game. The Blink Ball is motion activated. Simply strike to activate the LED light inside. Batteries are included but not replaceable. Approx. 10, 000 flashes before battery fades. Blink Ball can be used as a normal beach ball once the batteries have faded. Warning: Keep away from naked flames & other sources of heat.