The Kenko Auto DG Extension Tubes are a set of three individually sized tubes compatible with Nikon AF lenses. Use individually or stack multiple tubes together to enable existing Nikon lenses to focus closer than the normal minimum distance. The extension tubes create a set distance between the original lens and the sensor, ideal for creating macro images. The tube design is free of any additional elements, which allows the original optical quality of the Nikon lens to be maintained.The set contains one 12mm, 20mm and 36mm length tubes, and are compatible with Nikon AF lenses. Combine each one as needed based on the level of magnification required.