1Battery System: The automatic 140 amp dual battery isolator has the charging you need for a 2 battery system, which is like having 2 separate power sources for each battery. 2Performance: Dual battery isolation kit allows your accessories to run from a separate battery while keeping your main battery charged and ready to start your vehicle when you need it. 3Voltage Protection: When the input voltage is below 11V, the circuit breaks to protect the main battery from over discharge, and when the input voltage reaches 17V or more, it breaks to protect the battery from high voltage shock. 4Wide Application: Dual battery smart isolator suitable for a wide variety of vehicles, such as, cars, RVs, trucks, tankers, SUVs, ships, small boats, yachts. 5Install Detail: The battery isolation relay does not require a generator or ignition connection, no additional components are needed to complete the installation, and a full range of accessories are available to meet your needs.