The Automatic 140 Amp Dual Battery Isolator is all you need to charge Two Battery Systems. Voltage Sensitive Relay cuts in at 13.3 volts and cuts out at 12.8 volts to ensure your primary battery is always charged and ready to start your vehicle. It's like having two separate power sources for each battery while only having one alternator!Unlike other isolators on the market, the Automatic 140 Amp Dual Battery Isolator is IP67 Certified. This International Protection rating means that your isolator is safe for use even for your off-road needs in dusty, wet and unexpected extreme weather environments. Great for extreme vibration applications as well.This battery isolator suitable for 12V 140 Amp, Truck, SUV, RV, ATV, UTV, Boat and so on.Forget the traditional diode relays and so-called "solid state" devices that can you of almost 2 amps of output power! The Dual Battery Isolator is the unit designed with cutting edge programming to deliver performance - with ZERO sacrifice. This compact battery isolator was built ultra-small to fit almost anywhere! A under the hood to get close to your dual batteries.Cause your accessories to run from a separate battery while the engine is not working on your vehicle, and at the mean time holding your main battery charged and your vehicle always ready to work.Continuous Rating: DC 125AIntermittent Rating: DC 140APower Consumption: 10mA (Standby)/ 330mA(Engage) / 0mA (Storage)Terminal Studs: M6(1/4inch)colour: blackMaterial: ABSSize: 6.5cm x 6.5cm x 5cmPackage Contents:3 x 140 AMP Battery Isolator3 x Blue Ring Terminal12 x Screw3 x English manualOnly the above package content, other products are not included.Note: Light and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.