The translation ring is threaded on one side to fit the filter thread on the lens. One end of the translation ring is the completely standard lens end connection and the other end varies depending on the filter size. With the help of the translation ring, you can connect the lens to the camera frame with the filter thread, so you can take great macro shots with the kit lens, you don't need to buy an expensive macro lens for this purpose. Of course, it doesn't replace it, but impressive shots can still be taken.