By enlarging the viewfinder image by a quarter, it facilitates image composition when using lenses with focal lengths of 50mm and upwards. At the same time, it also improves focusing accuracy especially when using tele zoom lenses. The viewing magnifier is screwed into the camera eyepiece and attached to the carry strap eyelet with a small chain, protecting it from loss and damage. It comes with a leather to store it.

The thread adapter (24001) is necessary to use the magnifier with the Leica M10.