The Tamron 100-400mm F /4.5-6.3 Di VC USD (Model A035) is a highly portable, ultra-telephoto zoom lens with AF precision for shooting moving subjects with the utmost clarity.  Tamron’s proprietary eBAND (Extended Bandwidth & Angular-Dependency) Coating suppresses reflections, yielding vivid images of amazing clarity. And thanks to a lens barrel made primarily of magnesium, the 100-400mm boasts the lightest weight in its class*, making it ideal for handheld shooting over long periods of time.  Moisture-Resistant Construction and a fluorine-coated front element provide additional protection when shooting outdoors.