. The light gets its name from the four red LED bulbs that make up this light and manage to a, highly respectable, bright 44 lumen output. The light comes with its own mounting system that doesn’t require any additional cables or tools to be attached to the bike. Also you never have to worry about finding and changing batteries as the light comes with its own integrated USB plug which can charge the light via any standard USB port Features. 44 lumen light output35-degree beam angleWeighs 35g100% waterproof designUSB rechargeable with integrated plugRecharge time 4-5 hoursLithium polymer batteryIncludes tool-free mounting systemBuy Knog Lights from Chain Reaction Cycles, the World’s Largest Online Bike Store.