Fitted to water, water ballast and oil tanks and led to the upper deck to allow the escape of air when the tanks are being filled.
Ufakwa kumanzi, kwisizinzisi samanzi, nakumatanki e-oyile kwaye ukhokelelwe kumbundu ophezulu ukuze umoya ukwazi ukuphuma xa kuzaliswa amatanki enqanawa.