Zykkor Macro Bellows for Canon EOS EF Lens Film & Digital SLR, Canon EOS Cameras, Canon EOS 1d, 1ds, Mark II, III, IV 5D, 5D Mark II, 7D, 10D, 20D, 30D, 40D, 50D, 60D, Rebel xt, xti, xs, xsi, t1i, t2i, 300D, 350D, 400D, 450D, 500D, 550D, 1000D Macro bellows help toextenddistance between camera and lens. This way you can shorten the focus limit and increase the magnification. The fartherlensfrom the camera, the greater is the magnification of the subject. Light Tight, Black Bellows expands up to 150mm Includes Tripod mount socket, Ruled & Geared focusing rail, Smooth focusingwith Locking knob.