A drain plug is a crucial vehicle component that seals the oil pan, helping to maintain the engine oil level. It prevents leaks by ensuring oil doesn't escape during driving. Drain plugs are often made from durable materials like steel or aluminum to ensure long-lasting performance. They are easy to remove and install during oil changes, making them a critical part of routine vehicle maintenance. The proper functioning of a drain plug is essential to keep the engine well-lubricated and to minimize wear.