The 31mm Pro Auto Macro Extension Tube from Fotodiox is suitable for use with Canon EOS EF & EF-S Lenses for extreme close-up. It is an automatic tube that is able to communicate all electronic functions from the lens to camera including autofocus and auto-exposure. No other optical components are added, so the image will preserve the original optical properties of the lens.
The lens transforms into a macro lens while maintaining its optical quality. By placing distance between your camera body and lens, focusing distance is shortened and the effect of magnifying your subject is created.