PurposeUSED TO RELEASE THE PARKING BRAKE ON THE GOODRICH AND MESSIER-BUGATTI-DOWTY MAIN BRAKE ASSEMBLIES WHEN NO ELECTRICAL POWER IS AVAILABLE TO THE AIRPLANE. IT ALSO PROVIDES A LOAD CELL TESTING CIRCUIT (GOODRICH ONLY). ADDITIONALLY THIS TEST SET PROVIDES BREAAirplane787-10, 787-8, 787-9Usage CodeMAINTENANCE 