1The 250Amp battery isolator is a main battery saver used to combine two batteries when the alternator is charging (engine running) 2Isolate the two batteries when not charging (engine off) so that you can still start the vehicle 3Easy to install, only the power cord in and out. No need to try new equipment off road to discharge the vehicle's original battery 4Using magnetic latching relay, will not generate heat for a long time. Ultra low power consumption, quiescent current is less than 0.3mA, can be used for a long time 5Input voltage is 12V/24V working voltage and load voltage, peak current for 250A normally open Item Type: Dual Battery Smart Isolator Material: Aluminum alloy Purpose: Dual battery isolation relay Colour: Black Input Voltage: 12V/24V working voltage and load voltage Continuous Current: 250A normally open Peak Current: 250A normally open Automatic Connection Voltage (delay 5 seconds): 13.5V-16V (12V working voltage), 27V-32V (24V working voltage) Automatic Disconnection Voltage (delay 5 seconds): 12.5V Overvoltage: 16V/32V Size(LxWxH): Approx. 152 x 147 x 40mm / 6 x 5.8 x 1.6in 1 x Dual Battery Smart Isolator1. Please do not put the product under water.2. Do not use outside the rated voltage and current range.