Light large-aperture telephoto zoom lens, F2.8 constant aperture for extraordinary exposure and depth of field, Spectacular resolution from XA (Extreme Aspheric) and aspheric lens elements, Suppressed chromatic aberration from Super ED and ED elements, ED aspheric lens elements correct spherical and chromatic aberrations, Four XD (Extreme Dynamic) linear motors for fast, precise autofocus, Nano AR coating II suppresses reflections, flare and ghosting, Beautiful bokeh from 11-blade circular aperture and XA lens element, Dust and moisture resistant for robust reliability, Three customizable focus hold buttons, Linear Response MF for precise manual focus control, Instant auto/manual focus selection via AF/MF switch, Front fluorine coating prevents fingerprints, dust, water and oil, Built for both worlds: Ideal for still and movie creators, Focus, zoom and aperture ring with click on/off function,