This document summarizes the Canon 70-200mm f/2.8L EF Telephoto Zoom Lens USM. It has the following key features: - Focal length of 70-200mm with a maximum aperture of f/2.8. - Contains 18 lens elements in 15 groups including 4 UD glass elements to correct chromatic aberrations. - Closest focusing distance of 1.5m. It uses a rotating zoom system. - Known for its superb image quality and constant f/2.8 aperture, making it popular among professionals.