The Extender EF 1.4X III from Canon is designed for select Canon EF mount L-series telephoto lenses. It increases the focal length of a lens by a factor of 1.4x while still delivering superb image quality. It is ideal for photojournalists and wildlife, nature, and sports photographers who need to get close to distant and challenging subjects and it reduces the need to carry heavy telephoto lenses. The Extender EF 1.4X III features seven optical elements in three groups and all-optical elements have Canon's Super Spectra coating to reduce ghosting and flare. To facilitate the accurate transfer of imaging data between the lens and camera body, the extender features an integrated processor which ensures all focusing, metering, and ID information is available - allowing the photographer to capture balanced, well-exposed images. The extenders offer the exceptional build quality expected from Canon's professional products, and are resistant to both dust and water, allowing photographers to use them in extreme shooting conditions. The carefully positioned lens release mechanism makes it easy to mount the extender quickly, reducing the time the camera and lens are exposed to the environment.