The HL-EL135 has three LEDs and OptiCube lens technology for a wider, 150 candlepower beam with excellent visibility. With two AA batteries, the HL-EL135 will run up to 80 hrs on constant mode and up to 320 hrs on flashing mode, making it the perfect everyday commuter safety light. The light features Cateye\'s exclusive tool-free FlexTight mounting bracket that allows you to quickly and easily attach the HL-EL135 to virtually any handlebar. Key Features: Three LEDs OptiCube lens technology for a wider beam 150 candlepower beam 2 modes: Flash / Constant Runtimes: 320hr / 80hr Flextight bracket included 2 x AA batteries required