Trustfire Carbon Fiber MTB Bicycle Double Handlebar Extender Lamp Holder for Bicycle Lights Flashlights with Allen Key Carbon fiber and aluminum alloy material, strong and durable. With Allen key, it is easy to install on the bicycle. Stiff and sturdy, it can be used for a long time. It can be used for bicycle lights, flashlights and stopwatch installation. Suitable for mountain bike and other bicycles.