Headlight and tail light combo pack featuring a 65 lumen headlight and 30 lumen rear light. Modes include High stead Low steady Daylight pulse Nitelight pulse and Economic Flash for both lights. USB rechargeable - no batteries to buy or replace. Side illumination ports allow cyclist to be seen when riding across traffic lanes. Memory Function - Lights turn on at the last mode it was turned off. Power saving function- 10% power or less lights will automatically switch to lowest lumen output. Built in battery indicator- Red illumination = lower than 25% Green = fully charged