Genuine OEM Audi Belt Tensioner Damper, part number 057903133AB. This critical component is part of the engine's accessory drive system, designed to maintain proper tension on the serpentine belt and absorb vibrations. It ensures consistent power delivery to accessories like the alternator and A/C compressor. Weighing 0.551 kg with dimensions of 0.15m x 0.07m x 0.073m. Opting for a genuine OEM belt tensioner damper guarantees factory-specified spring rates and damping characteristics, crucial for preventing belt slippage, premature wear, and accessory damage.