The Fuji XF 2x TC WR Teleconverter mounts between your camera body and lens in order to give your lens more reach through magnification. It features a built-in microcomputer for seamless communication among camera body, lens and extender, including metering, autofocus, and image stabilization (on compatible lenses). Note that this extender reduces your maximum aperture by 2 stops. It is recommended that you attach the extender to your lens and then attach the pair to your camera body. Extenders allow photographers to shoot from greater distances without having to resort to using larger and longer lenses. Teleconverters are useful for shooting sports, wildlife, and ceremonies.