The Pentax SMC DA L 50-200mm f/4-5.6 ED is an impressive lightweight and compact mid-range 4x telephoto zoom lens. Ideal for the photographers desiring a broad zoom range without the pressure of heavier lens. Simple yet functional design of the SMC DA L 50-200mm f/4-5.6 ED concerts Extra-low Dispersion glass element and two aspherical lens elements for true-to-life image reproduction. Its lens construction is comprised of 11 elements in 10 groups, nine aperture blades, and has an equivalent 76.5-307mm focal length in 35mm format. Designed to fit Pentax DSLRs with APS-C 23.5x15.7mm CCD sensors for optimal performance, the lens also features Super Protect Coating.