Xit XTETS Auto Focus Macro Extension Tube Set for Sony SLR Cameras (Black)Short Description Includes 3 Tubes Auto Focus You Pick Your Magnification In The Box Macro Extension Tube Set (13MM 20MM 36MM) SONY Long Description Designed to enable a lens to focus closer than its normal set minimum focusing distance. Magnifying your subject (making it appear larger in the viewfinder and in your pictures) Designed with all the circuitry and mechanical coupling to maintain auto focus and TTL auto exposure with most Sony mount lenses