This is an electrically-powered zoom adapter that can be attached to compatible EF lenses for seamless zoom operation. With it, you can carry out zooming at a defined speed â which is difficult to achieve manually â just by operating the zoom lever. A flick of the speed mode switch allows you to adjust the zoom speed to suit your shooting requirements. Remote control of the zoom function is also possible as both the Camera Connect app and the EOS Utility PC software are supported. Using 4 easily-obtainable AAA batteries for drive power, it is not only compact, lightweight and portable, but can also be easily attached to the lens.