FODSLR Red Metal Auto Focus Macro Extension Tube Set for Canon SLR Cameras CANON EF EF-S Lens This Macro Extension Tube Set includes 3 extension tubes:13mm,21mm,31mm This macro extension tube set is suitable for all Canon EF EF-S and IS series lenses. Transform your Lens into a Macro Lens moves the lens from the film or digital sensor. The closer the focus is, the greater the magnification This extension tube does not affect image quality as there is no optics inside In comparison, a close up filter is often blamed for degrading the quality of image. Auto-focus function can operate