This is a Canon EF 28-135mm f/3.5-5.6 IS USM lens for Canon cameras. It has a maximum aperture of f/3.5-5.6 and can be used for both auto and manual focus. The lens is compatible with Canon cameras and has a mount for Canon IS. It is a USM lens with a fixed/prime focal length type and a product line of Canon USM. This lens is perfect for SLRs and is in excellent working condition.