The Canon Tripod Mount Ring is the tripod collar for the Canon EF 100mm f/2.8 IS Macro Lens. By adding a tripod collar to your lens you can achieve a better balance on a tripod. The tripod ring also makes a big difference in minimizing vibrations. In addition, rotating the camera will now be much easier and faster. The ring is very easy to put on and take off the lens as the lens does not need to be removed from the camera.