This kill switch for car uses a new type of relay that controls circuit disconnection and cut-off by magnetic principle, with a standby current of 3mA, which is more energy-saving. Automatic Cut Off - If the voltage is lower than 11.8V, the remote kill switch automatically cut off the power supply after 120s to save electricity, if the voltage is higher than 13.2V, the remote control be disabled to prevent accidental action to shut off the power while driving, and the power supply can only be controlled by the button on the switch. Easy Installation - The power shut off switch uses a negative connection to stable performance. Please remember to turn off the power before installation. Protect the Battery - Using this car battery kill switch can avoid power consumption due to long-term parking, good point of electronic equipment, line aging, forgetting to turn off the light, etc. It can effectively protect and prolong the life of car battery. It can effectively protect and prolong the