Bicycle Light-Frog gem tail lamp pack of two pieces Easy Installation: Our premium bicycle lights can be installed in seconds without the need for any tools or other equipment. Add a light to your bike, backpack, helmet or other areas for maximum safety. Premium Aluminum: AlloyDurable and Flexible Silicone Band,Water Resistant and 2 Batteries per Light,battery Life - 50 Hrs on Steady, 150 Hrs on Flash Three light modesFast Flash, Slow Flash, Steady Satisfaction Guarantee:If you arent completely happy with our LED lights, simply return them within 30 days for a full, no questions asked refund.