ZCI Zero Contact Interface Universal ModuLite Universal Trailer Light Power Module. ZCI sensor technology and direct connection to the tow vehicle battery, eliminates all electrical connection and interference with the tow vehicle electrical system. Vehicles with 12 volt system only. Features NO CUTTING OR SPLICING VEHICLE WIRING!. Isolates Trailer Light Operation from Tow Vehicle's Electrical System. Works with 2 or 3 wire systems. Works with PWM or Multiplexed systems requiring 2 or 3 wire hookup. Rated for up to 4.2 amps for turn/stop 7.5 amps for taillight trailer circuits. Works with low side switched vehicles. Integrated auto resetting short overload protection. Robust design allows for interior or exterior mounting ZCI sensor technology and direct connection to the tow vehicle battery, eliminates all electrical co NO CUTTING OR SPLICING VEHICLE WIRING!. Isolates Trailer Light Operation from Tow Vehicle's Electric Works with 2 or 3 wire systems. Works with PWM or Multiplexed systems requiring 2 or 3 wire hookup Rated for up to 4.2 amps for turn/stop 7.5 amps for taillight trailer circuits. Works with low sid Integrated auto resetting short overload protection Robust design allows for interior or exterior