High-performance, L-series telephoto zoom lens combining light weight and compactness with an f/4 maximum aperture. Inner focusing and the ring USM enable quick and quiet autofocusing. Also, a circular polarizing filter can be attached and used without difficulty because the front lens element does not rotate during focusing. The tripod collar (sold separately) is the same one used with the EF 300mm f/4L USM. L-series quality The L-series is Canon's flagship professional lens range, representing the best in precision-designed EF optics. L-series lenses combine superior performance with superlative handling, and are resistant to dust and moisture. Professional features A maximum aperture of f/4 is available at all focal-length settings, ensuring shutter speeds do not change as the lens is zoomed. A non-rotating front element simplifies the use of filters, such as polarizers and grads. Ultrasonic focusing A ring-type ultrasonic motor drives autofocus extremely quickly, and in near silence. Excellent holding torque ensures the point of focus is reached accurately, without overshooting. Furthermore, full-time manual override is available, making it possible to adjust focus without leaving AF mode. Super Spectra coating Super Spectra coatings ensure accurate color balance and enhance contrast. They also reduce flare and ghosting - a common problem caused by light bouncing off a camera's sensor.