Pentax DA 50-200mm f/4-5.6 ED Lens for Pentax and Samsung DSLR Cameras 50-200mm telephoto zoom lens with f/4-5.6 maximum aperture for Pentax DSLR cameras Incorporates extra-low-dispersion (ED) glass lens element and 2 aspherical lens elements Responsive Quick-Shift Focus System allows instant shifts from auto to manual focus Includes lens hood to minimize flare and ghost images; 4x zoom coverage in telephoto range Measures 2.6 inches in diameter and 3.1 inches long; weighs 9.2 ounces