The high performance DA* 200mm ED (IF) lens incorporates an SDM system which creates a smoother quieter auto focus. Featuring a Quick-shift Focus System switching from auto focus to manual is instantaneous. Developed specifically for PENTAX digital SLRs the DA* 200mm ED (IF) SDM lens has PENTAX SP coating which protects the exposed lens elements and a focal length equivalent to 300mm in the 35mm format. Weather and dust resistant it's the perfect lens for extreme weather conditions. 200mm High performane telephoto lensWeather resistant and dust resistant.