Genuine OEM Hyundai Cylinder Block Rear Cap, part number 214122M000. This cap is designed to seal an opening at the rear of the engine's cylinder block, typically covering a passage or access point. Its primary function is to prevent oil leaks and protect the internal engine components from contaminants. Using a genuine OEM rear cap ensures a precise fit, proper sealing, and resistance to engine fluids and temperatures, which is critical for maintaining engine integrity and preventing costly leaks.