AeroShell Oil W100 is an ashless dispersant oil specifically developed for aviation piston engines. It combines non-metallic additives with selected high viscosity index base oils to give exceptional stability, dispersancy and anti-foaming performance. No general rule exists for every engine type when choosing the correct grade of oil; however, based on the average ambient outside temperature at engine start-up one of the most common grades is SAE 50 which equates to AeroShell oil W100 for temperate regions 59 - 86°F (15 - 30°C). Ships ground economy to the USA lower 48 States only.