Technologically advanced nighttime LED fetch ball. Holds up to the best arm or ball launchers around. This robust rubber ball has a protected inner core that contains an advanced motion-activated LED module with bright red or color-changing Disc-O LEDs， and it turns on with a simple bounce. It also features an auto shut-off function after 10 minutes without a bounce (5 minutes of glow followed by 5 minutes of flashing)， giving you or your dog time to find it if one of you becomes distracted. The molded， shockproof， removable polycarbonate core houses the LED/battery module and screws securely into place creating a waterproof seal. The same size as a tennis ball and invincible to water or slobber， this tough little ball floats， and is great for the dog who loves to swim. The unique grooved design on the surface creates a bite friendly exterior that is easy to pick up for small and large dogs alike. Powered by replaceable， long-lasting batteries， you can have up to 35 hours of playtime.