The failure-prone harnesses on BMWs are known to develop corrosion which increases electrical resistance, which in turn, increases the temperature of wires to the point where connectors start melting. When this happens, the voltage regulator (and most likely the stator) is failing incurring steep repair expenses. Our bypass voltage regulator brings back the renowned RMSTATOR Series technology designed to bypass the main wiring harness and connect the voltage regulator directly to the battery. This configuration has demonstrated a major increase in voltage regulator reliability in real life scenarios over the years. Series Technology Significantly lowers regulator and stator temperatures for more accurate voltage regulation, and increased reliability of your charging system components PRO-FIT System Includes everything required to perform a RMSTATOR-style professional installation: part connectors, bypass harness & dielectric connector grease.