NiteRider Lumina 400 LED Headlight and Solas 30 Lumen USB Tail Light - Performance Exclusive Internal Li-Ion battery with &quot;Intellicharge&quot; recharges in only 3 hours via USB cable Built-in indicator light switches from red to blue when the battery is fully charged High-powered 400 lumen Cree LED produces more light with less power and less heat Custom made reflector and Borofloat lens work together to minimize light transmission loss and maximize light output for excellent optical clarity -- superseding internal reflectors or standard glass lenses