By Bestbuy.com

Fotodiox - Automatic 21mm Macro Extension Tube Section - Compatible with Canon EF/EF-S Mount Cameras for Close-up Photography

Macro extension tubes are a wonderful alternative to expensive macro lenses. By placing distance between your camera body and lens, focusing distance is shortened and the effect of magnifying your subject is created. Macro extension tubes are an affordable and simple way to turn any existing lens into a macro lens.