This master power window switch serves as a direct aftermarket replacement part for your vehicle’s original window control unit, with OEM reference number 2518300390 (A2518300390). Designed to fit perfectly on front left driver door, this control panel manages all power window operations and side mirror adjustment functions. Manufactured following original equipment specifications, this switch adopts robust internal conductive components and premium plastic housing to resist daily wear, temperature fluctuation and long-term frequent operation. Every button is precisely calibrated to deliver sensitive, responsive operation, eliminating unresponsive or stuck window control faults caused by aging factory switches. No complicated modification is required during installation; this unit supports plug-and-play assembly to match the original wiring harness position, greatly saving your maintenance time. This window lifter control switch is engineered for compatible vehicle models including GL450, GL550, R350 built on W164 and W251 chassis. Strict quality inspection is carried out for every finished unit before delivery to guarantee stable performance. This replacement switch effectively restores full functionality to your vehicle’s power windows and side mirror controls. If your original switch suffers problems such as delayed window response, broken buttons or mirror control failure, this assembly is an ideal cost-effective repair solution. One piece of master power window switch is included inside each package. Please verify your OEM part number and vehicle chassis model before ordering to confirm proper compatibility.