Ring Automotive RMS4 This unit has been designed to aid the motorist with his power requirements. As we use more & more devices in a car we end up with less & less place to plug them in which is how the Ring RMS4 came into being. the Unit Boasts the following features 3 Accessory sockets, Battery analyser to show power charge level, Illuminated Cigarette lighter socket, Coiled power cable with fused plug. Mounting arms for permanent fixing. Maximum current rating 8amp.