PurposeUSED TO PRESSURIZE THE WING DRY BAY TO CHECK FOR FUEL LEAKS THROUGH ANY FLAME ARRESTOR FITTING IN LOWER WING SURFACE AND BY PLUGGING THE OTHER(S)Airplane747, 757, 767, 777-200, 777-200ER, 777-200LR, 777-300, 777-300ER, 777F, 787-10, 787-8, 787-9Usage CodeMAINTENANCE 