This superb SAL-55200 telephoto zoom lens for your Alpha DSLR camera has a smooth and silent AF operation with a built-in motor to handle themed range to telephoto zoom shots. In 35mm equivalent, it covers midrange 82.5mm to 300mm telephoto zoom (4x), ideal for shooting portraits, sports, wildlife and more. Please note: DT lenses are not recommended for use with the DSLR-A900. FEATURES: SteadyShot INSIDE In-Camera Image Stabilization - A major reason for its compact, lightweight lens design is the benefit of SteadyShot INSIDE in-camera image stabilization, built into every alpha DSLR camera -- and enabling lenses to eliminate the extra weight and expense of in-lens stabilization mechanisms. ED (Extra-low Dispersion) Glass - To reduce chromatic aberration at telephoto extension, correcting certain wavelengths of light for sharp, clear images with well defined colors. DT Lens Design - A more compact, lightweight lens designed specifically for the APS-size CCD imager used in some Sony alpha DSLR cameras. Circular Aperture - Because aperture blades form a near circle at the wide openings used for low-light shots, spot-light sources have a pleasing circular defocused effect. Smooth Autofocus Motor (SAM) - The built-in Smooth Autofocus Motor (SAM) eliminates the need to use a mechanical coupling system in the camera body to transfer auto foucs (AF) drive power and control signals to the lens. Instead, AF control signals from the camera body are sent to the lens-mounted SAM unit, which drives the focusing lens group directly, helping to assure smooth AF response.