1 Lot of 2 New Surplus Eastman Skydrol Fire-Resistant Hydraulic Fluid QT 500B4. We found these in an inventory we recently purchased. The Eastman Skydrol Hydraulic Fluid contains the same breakthrough anti-erosion additive and acid scavenger found in Skydrol LD-4 and is the most worker friendly. This hydraulic fluid is also erosion resistant and less irritating. Cessna, Boeing, Gulf-Stream, Embraer and Lockheed all approve the use of this hydraulic fluid.