The Automatic 140 Amp Dual Battery Isolator allows you to charge two batteries efficiently using a single alternator. The voltage sensitive relay activates at 13.3 volts and deactivates at 12.8 volts, ensuring your primary battery remains charged and ready to start your vehicle. This system functions like having two independent power sources while utilizing only one charging source.Unlike other isolators, the Automatic 140 Amp Dual Battery Isolator is IP67 certified, providing protection against dust and water ingress. This makes it suitable for off-road, marine, and outdoor applications where exposure to harsh environments such as moisture, dirt, and extreme weather conditions is expected. It is also designed to withstand high vibration environments.This isolator is compatible with 12V systems up to 140 amps and is ideal for use in trucks, SUVs, RVs, ATVs, UTVs, boats, and similar vehicles.Avoid outdated diode relays or inefficient "solid state" devices that may waste power. This unit delivers reliable performance without compromise. Its compact design allows for easy installation in tight spaces, making it perfect for under-hood setups to support dual battery configurations.It enables accessories to run from a secondary battery when the engine is off, while preserving the main battery for engine starting and critical vehicle functions.Specifications: - Continuous Rating: DC 125A - Intermittent Rating: DC 140A - Power Consumption: 10mA (Standby) / 330mA (Operation) / 0mA (Storage) - Terminal Studs: M6 (1/4 inch) - Color: Black - Material: ABS - Size: 6.5cm x 6.5cm x 5cm Package Contents: 1 x 140 Amp Battery Isolator 1 x Blue Ring Terminal 4 x Screw 1 x English Manual Note: Light and screen settings may cause slight variations in color representation. Measurement may vary by +/- 1-3cm.