This lens is a telephoto zoom lens equipped with the world's first extender mechanism, as lens for a camera with interchangeable lenses. A zoom area of 200-400 mm based on 35 mm conversion can be switched to a zoom area of 280-560 mm using a 1.4x extender, through a simple lever operation. In addition to a broader zoom thanks to a built-in extender, it is possible to prevent infiltration of dust and water droplets when replacing lens and attaching the extender. This lens is well-reputed for use capturing sports photos and photos of wild animals.