The Auto Extension Tube Set for Canon EF/EF-S Mounts and Lenses from Vello allows your lens to focus closer than its normal minimum focus distance. By placing distance between your camera body and lens, focusing distance is shortened and the effect of magnifying your subject is created. Extension tubes enable macro performance for lenses not otherwise able to focus that close, and are also suited for close-up portraiture. The Auto Extension Tube Set for Canon EF/EF-S Mounts and Lenses contains three extension tubes of 13, 21, and 31mm lengths. They can be used individually or together in seven distinct combinations to create the desired magnification effect. For closer focusing use the larger extension tube or stack the tubes together. Extension tubes have no optical elements so do not degrade the quality of your lenses.
These tubes are fully automatic tubes in that they are able to communicate all electronic functions from lens to camera including autofocus and auto exposure. They are built with metal lens mounts for durability and longevity and enable you to convert almost any lens into a macro lens at a fraction of the cost while maintaining the lens' original optical quality.