This combo set includes Cygolite's Dice 150 headlight and the Dice 50 tail light. The Dice stands out in broad daylight with its intense lightning-like flashes. It even senses day and night, automatically switching to the optimal flash mode. Engineered for road cyclists, it uses a low profile, flexible mount that's designed for most handlebars including aero bars. Compact, easy to install and USB rechargeable, these lights have excellent run time for their size. Depending on mode, the Dice 150 Headlight runs 3/4 to 24 hours, and the Dice 50 Tail light runs 1.5 to 65 hours.