This adapter makes it possible to us classic B4 lenses on a Sony F5 or F55.
Mount 2/3” B4-mount lenses to a Sony F5/F55 single sensor camera, while maintaining the same angle of view the lens exhibits on a 2/3” prism block camera. The adapter provides the communication between the lens and the camera, passing metadata. The adapter allows your camera to display lens data information, such as focus, zoom, and iris in the viewfinder. The adapter supports chromatic aberration compensation using ALAC-2 for select lenses, and you can assign the “RET” button allowing you to call functions such as Expanded Focus and last clip review.