Canon EOS EF 24-85mm F3.5-4.5 USM Ultrasonic Zoom Lens is a versatile zoom lens designed for Canon EOS cameras. With a maximum aperture of f/3.5, it allows for great low-light performance. The lens features Ultrasonic Motor (USM) technology for fast and accurate autofocus, and can also be manually focused. It has a focal length range of 24-85mm, making it suitable for a wide range of photography styles.