A macro extension tube is a wonderful substitution for the expensive macro 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. Fotodiox Pro Auto Macro Extension Tube for Canon EOS 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.