One of the finest telephoto zoom lenses in Canon's EF line, this 70-200mm f/2.8 lens offers comparable optics to a single focal-length lens. The lens employs four UD-glass elements to minimize chromatic aberrations, creating sharp, high-quality images regardless of the application. The constant f/2.8 maximum aperture, meanwhile, makes the lens extremely popular among professionals. Other features include an inner focusing system with an Ultra Sonic Motor (USM), a 4.9-foot close focusing distance, and a 77mm filter size. The lens--which is compatible with EF 1.4x II and 2x II extenders--carries a one-year warranty.