Whether you're commuting when daylight is at a premium, or you're pedaling out pre-dawn base miles, you probably blowing through eight packs of batteries like thorns on tires. So, to save you some cash, without compromising on safety. NiteRider create the new Solas 2 Watt USB Tail Light. The Solas provides four modes (two flashing and two steady) and a "Group Ride Mode" for those who need to feel visible in the pack. Rechargeable via USB connection, the Solas will last around 36 hours on low-steady mode. 4. 5 hours on high-steady. 18 hours with a single flash, and 7 hours with a double flash. The bright two watt bulb is visible for blocks, increasing your visibility to motorists when office meetings run late. The NiteRider Solas 2 Watt USB Tail Light comes with a bike mount and a USB charger.