eCostConnection Auto-Focus Macro Extension Tube Set for Canon 5D Mark II, Mark III , 6D, 70D, 7D, 60D, Rebel T2i, T3i, T4i, T5i, SL1 Cameras & Microfiber Cloth 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) Tube Set Includes: 13mm, 21mm, & 31mm extension tubes Designed with all the circuitry and mechanical coupling Lightweight design Tubes can be used individually or in any combination to obtain the desired magnification