Genuine OEM Hyundai Belt Tensioner Assembly, part number 252802G115. This essential engine component is responsible for maintaining the correct tension on the serpentine or accessory drive belt, which powers components like the alternator, power steering pump, and air conditioning compressor. It is typically located on the engine block, part of the accessory drive system. Weighing 1.02 kg and measuring 0.145m x 0.095m x 0.09m, it is constructed from durable metal with precision-machined pulleys. Using a genuine OEM tensioner ensures factory-specified spring rates and pulley alignment, preventing premature belt wear, slippage, and potential damage to engine accessories.