Genuine OEM Audi Timing Chain Upper Guide Rail, part number 079109469AD. This guide rail is a crucial component within the engine's timing system, responsible for guiding the timing chain and maintaining its proper tension and alignment. It is positioned in the upper section of the timing chain assembly. Weighing 0.0485 kg and measuring 0.195m x 0.035m x 0.028m, this genuine OEM guide rail is manufactured from high-quality, wear-resistant material to withstand constant friction and heat, ensuring precise valve timing and preventing catastrophic engine damage.