Genuine OEM Audi Drive Belt Tensioner, part number 06E903133AG. This crucial component is designed to maintain the correct tension on the engine's accessory drive belt, ensuring consistent power delivery to vital accessories such as the alternator, air conditioning compressor, and power steering pump. It is typically mounted on the engine block or a bracket, allowing the drive belt to run smoothly without slippage or excessive wear. Constructed with a durable metal body and a robust pulley, this tensioner weighs approximately 0.74 kg. Choosing a genuine OEM tensioner guarantees factory-specified spring rates, bearing quality, and precise alignment, which are critical for preventing belt slippage, reducing noise, and extending the service life of the drive belt and connected accessories.