NiteRider's Lumina 750 & Solas Taillight Combo will guide you safely home. This bright light puts out up to 750 lumens for up to 18 hours and weighs in at only 172 grams! It attaches easily onto handlebars (up to 31.8mm in diameter) or a helmet so you can be ready to head out the door in no time. There are five modes to choose from: high, medium, low, energy-saving walk, and flash. You can charge it off a computer's USB port and, should you throw it in a bag for later use, the Lumina's lock out mode ensures it won't accidentally turn on and waste battery life. And, this combo features the Solas, which boasts a 2-watt LED, produces 30 lumens, and has 4 settings including a daylight safety flash mode to keep you visible to others.