1The replacing reference OE number is 17137601950, 17137647284, 17137578439, 603831. 2The coolant bottle is a replacement for 5 series 523i F10, F18 2009/062011/08 and other models. 3Store excess pressure and coolant as your radiator heats up, help to make radiator full at all times and more efficient and effective. 4If your coolant is low, there may be a leak, using a pressure tester (not included) to check the system for smaller hard to find leaks. 5If your recovery tank is damaged, replace immediately to avoid a catastrophic cooling system failure.
