The Arri follow focus system provides smooth movement of the focus or zoom position of your lens for slick transitions and accurate focus tracking. Arri is a globally renowned name and the MFF-2 follow focus system is compatible with most cine lenses. We can also add geared rings to stills lenses. Worried about Nikon focus turning the other way? The Arri follow focus system has a reverse gear for use with Nikon and Zeiss optics.