This specification covers the requirements for aircraft hydraulic@ self-sealing@ quick disconnect couplings for use in 5000 and 8000 lbf/in2 (gage) lightweight hydraulic systems. Classification: Hydraulic self-sealing@ quick disconnect couplings shall be of the following classes and types: a. Class 5000 - 5000 lbf/in2 (gage) Operating Pressure (psi) b. Class 8000 - 8000 lbf/in2 (gage) Operating Pressure