The CTAMPPASSTHROUGH is an amplifier retention adapter that converts a new head unit’s high-level audio outputs into low-level signals compatible with the vehicle’s original amplifier. It reduces the output level from the aftermarket stereo so the factory amplifier can be retained and controlled.

The lead features a single 8-way ISO connector designed to sit between the new harness and the head unit power connection. It is intended for use with a stalk harness that provides an amp remote output and is especially suitable for Mazda Bose and Saab Bose systems that provide OEM low-level pre-amplifier signals.