Magicshine Seemee 100AD Radar Taillight. Features: Radar intelligently identify approaching vehicles and alert with a brilliant flash PelotonSync Flash Intuitively harmonizes flash patterns among nearby compatible taillights, amplifying visibility and team style on the road LightSync Control technology, synchronizes Seemee 100AD with compatible Magincshine front lights for intelligent one-touch control via remote 700mAh battery lasts up to 18 hours on a single charge lPX6 waterproof rating guarantees continuous operation in the harshest conditions USB-C rechargeable Specs: Model:Seemee 100AD Lumens:100 Modes:6 Rechargeable:Yes Color:Black Weight:38g