Mobil Aero™ HF

Mobil Aero HF is formulated for aircraft systems where use of hydrocarbon-based hydraulic fluids is required. They are low viscosity products, high VI (viscosity index) fluid with excellent low temperature properties, good anti-wear performance, and good chemical stability. Mobil Aero HF is composed of mineral base oil stock and contain shear-stable VI improvers.

Mobil Aero HF meets "super-clean" requirements required by modern aircraft hydraulic systems. It is intended primarily for military aircraft, but it is also used as a hydraulic fluid for small private and commercial aircraft, and as a strut fluid in landing gear of large commercial aircraft.

https://www.exxonmobil.com/en/aviation/products-and-services/products/mobil-aero-hf-series