Drain Plug (part number UG526) which has a number of applications, including the engine, gearbox,radiator and differential sumps as well as some fuel fank drains.  

Our coolant -26°C is a ready-to-use engine coolant that provides reliable protection against freezing, overheating and corrosion. The coolant protects the cooling system down to -26°C and is suitable for use in many modern and classic engines, including Rolls-Royce and Bentley models with conventional liquid cooling systems.