Voltage stabilizer's so here is some backround on them. They are a unit you hook up to the positive and negative terminals of your car battery to stabilize the voltage. Stabilizing voltage is said to help the car's ecu, which in turn results in the following benifits:
Improved audio quality.
Increased torque and response and power.
Stabilized idling and improved engine kick over.
Increased headlight brightness.
Improved fuel economy.
Improved battery life.