"You should buy this Oil Drain Bolt Assy."

The sump plug, also known as the oil drain plug, is a critical component located at the bottom of the engine's oil sump or oil pan. It allows for the drainage of engine oil during oil changes or maintenance. Typically made of metal and equipped with a sealing washer or O-ring to prevent leaks, the sump plug is threaded into the oil pan and can be removed to let old oil flow out.