Genuine OEM Audi AdBlue Supply Metering Line, part number 4H0131984AD. This critical component is responsible for accurately delivering AdBlue (Diesel Exhaust Fluid) from the reservoir to the injection point in the exhaust system, facilitating the selective catalytic reduction (SCR) process. It is typically located in the front section of the vehicle's emissions system. Weighing 0.335 kg and measuring 0.37m x 0.26m x 0.07m, this line is designed for precise fluid transfer. Choosing a genuine OEM metering line ensures correct routing, material compatibility with AdBlue, and reliable fluid delivery, which is essential for maintaining emissions compliance and system efficiency.