ISO Line Output Converter. (LOC) Provides four channel phono/RCA line level outputs from the head unit speaker level outputs. Line signal level maximum is about 2V p-p, and with capacitor-based galvanic separation of the head unit and external amplifier. A separate GND wire on the line signal side provides possibility for extra shielding if necessary. This is a very small and convenient harness compared to other brands, and use the same LOC device as in our other harnesses for use with the original Porsche amplifiers.