The Exposure RedEye Micro Rear Plug In LED Light is an extremely compact rear light which you can easily attach onto the back of your Exposure front light so you can also be seen from behind. This small LED light is compatible with the Joystick, Sirius or the Diablo front light with Smart Port Technology. This rear bike light is extremely compact, so it will fit into a jersey pocket or a saddle bag. This is useful if you ever find yourself riding in low lighting conditions. When you turn the light on it will emit a low light so it won't dazzle the people behind you but it will help to increase your visibility.Exposure RedEye Micro Rear Plug In LED Light FeaturesAttachment: Plug-in systemCompatible with: Equinox, Diablo SYNC, Diablo, Axis, Joystick, Sirius, ZenithType: Rear LED LightLength: 31.00mmHead Diameter: 12.00mm