About this item: [Manual State Function]: Long Press the button for 3 seconds, the BLUE led will be On, and the manual mode is on. Press the button each time, you can complete the circuit connection and disconnection. Circuit switched on the red indicator, voltmeter lights up at the same time. Switched off the red indicator, voltmeter lights off. [Auto State Function]: Long press the button for 3 button again, the BLUE led will be Off, the Auto mode is on. Voltage exceed 13.3V: Circuit will be automatically connected. Voltmeter & Indicator ON. Voltmeter lower than 12.7V: Circuit will be automatically disconnected. Voltmeter & Indicator Off. [Voltage Display]: This dual battery isolator is constructed with a voltmeter which will display the real-time voltage. If you connect 2 batteries, then the voltmeter will display the battery that has high voltage. The smart battery isolator is universal fit for truck, UTV/ATV, boat, marine, bus, etc. [Voltage Sensitive Relay]: Cut-in voltage: 13.3V and Cut-out voltage: 12.8V. the main battery is always so that you 't worry about the the battery will drain out and stuck on the road. Very convenient and safe to use. [Pressure Protection]: Input voltage lower than 11V or Input voltage more than 17V: Circuit will be automatically disconnected so as to protect the main battery from over discharging. Voltage Sensitive Relay VSR Smart Dual Battery Isolator Kit Real-time Voltage Display Built with a voltmeter display, which can help you read the real-time voltage. Voltage:12V Charging Current:90-120 Amp Continuous, 160 Amp Current Draw: Charging 250 Amp, Standby 10mA Cut-in Voltage: 13.3V Cut-out Voltage: 12.8 Cut-out Delay: 3-5 Seconds Protection: Surge (Spike) Waterproof: IP67 The battery isolator kit fits with your cars, boats, trucks, and any other electrical vehicles. Compact and Convenient to carry. Material: ABS colour: black Package Contents: 1 x battery isolator Only the above package content, other products are not included. Note: Light reflection 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.