AeroShell Oil 100 is a straight mineral oil blended from selected high-viscosity index base oils. This piston engine oil does not contain any additives except for very small amounts of pour point depressant (which aids to improve fluidity at very low temperatures) and an anti-oxidant. AeroShell Oil 100 is approved for all aviation piston engines of civil aircraft when the use of an oil not containing a dispersant additive is required; however, they should also be used during the break-in of a new aviation piston engine or those recently overhauled. AeroShell Oils 100 is produced to meet fully the SAE specification J-1966 Grade SAE 50.