This EF-R3 0.71 Speed Booster Adapter from Viltrox allows a Canon EF-mount lens to be used on a Canon RF-mount camera body and select cine bodies. A 0.71x optical multiplier is built into the unit, and electronic communication between the camera and lens is supported, enabling autofocus, image stabilization, and Exif data transfer. With some lenses, maximum focusing range maybe affected as the distance from the lens to the camera's sensor is slightly changed, and there is a 1-stop increase for the camera over the lens's aperture range. Additionally, the functions of some lenses are not fully available depending on the camera body. A micro-USB Port is provided for firmware upgrades, and the adapter features a removable foot with a 1/4"-20 tripod socket for easy mounting.