DS EN 3645-004:2007 Aerospace Series - Connectors, Electrical, Circular, Scoop-Proof, Triple Start Threaded Coupling, Operating Temperature 175 Degrees C Or 200 Degrees C Continuous - Part 004: Receptacle, Hermetic, Square Flange Mounting - Product Standard Defines the characteristics of square flange hermetic receptacles in the family of circular electrical connectors with triple start threaded coupling.