The 1-4G model includes a metal box. The 1-GR model comes without a backbox and is intended for use with a front-mounted Carlon old plastic box or mud ring. (*box/ring is not supplied by SeeLess)The 1-4GR model is recommended for applications with keypads. The main advantage of this model is access to the backbox and ring from the front of the mount, making them easy to adjust after the platform is in the wall.