The Canon Extender EF 2X III is designed for select Canon L-series telephoto lenses. The extender is perfect for photojournalists, nature and sports photographers who need to get close to distant and challenging subjects. The Extender EF 2x III increases the focal length of a lens by a factor of 2x while still delivering superb image quality. To ensure the best possible image quality in all shooting conditions, it also combines enhanced environmental protection, redesigned optics and improved data communication between lens and camera.