Aux Drivers are required for auxiliary ports on SL Modules and HP Modules. Each Aux Driver works with two individual outputs. The SL and HP Modules each have four auxiliary ports. Aux Drivers can also be used on any SL ports. Aux Drivers switch the positive (high) side of the circuit. This makes it useful where the other side of the LED is grounded, as are most stock lamps on a car.
Two types of Aux Drivers are available: Type A and Type B. Type B are the same as Type A except that they allow an "OR" input. This is useful for situations where you want the car's signal to always be able to turn on the light. Examples: Side Markers, Backup Lights, etc.