These unique 3-D glowing and flashing pendant necklaces continue working longer up to 16 hours on one battery life. You get 3 different lite effects: 1. Quick Flashing up to16 hours 2. Slow Flashing up to 16 hours 3. Steady Glow up to 8 hours. Also available as a “Constant Glow” 3-D pendant necklace with blue LEDs. Necklaces come with on/off switch. Batteries included.