High Quality 52mm To 77mm Step Up Ring By DragonFly Optical
There are three types of "rings": step-up, step-down, and macro coupler that are also referred to as reverse rings. Except for macro couplers, the step-up and step-down rings have one end (with male thread) to be mounted on the camera lens and the other end (with female thread) is used for accepting filters, another ring or other accessories. A ring has two size markings in millimeter such as 28mm-37mm, 49mm-52mm, 77mm-72mm and so on. The first number is the size of the thread that is closer to the camera lens (i.e., the male thread), while the second is the size of the thread of the farther end (i.e., the female thread)