Yes, it will work with both. If the steady grip does not contain the 3 pin gimbal connection plate, the small power cable will need to be used with the CGO3. If the steady grip does contain the gimbal connection plate as well as the CGO3, the camera can be powered on by simply affixing the camera to the steady grip. Some older CGO3’s do not have the gimbal connection plate so the small power cable would have to be used regardless. As far as the CGO2 goes, it never had a gimbal connection plate so the 3 pin connector that is already fastened to the camera will provide the power needed. Just install that male connector into the female connector on the under side of the steady grip.