Rail tanker loading/unloading couplings are designed to be mounted to pipe stubs on rail tankers. Most of these couplings has a female thread with a nut (e.g. M130x6) and a flat rubber seal, whereas at the other end there is a hose tail, CAMLOCK coupling adapter or BSP male thread, 4″ or 3″. The couplings are made of aluminium or brass (available in stainless steel as well). The rail tanker loading/unloading couplings are widely used in fuel, petrochemical and chemical loading/unloading applications.