Abstract: A single-point connection apparatus for a closed fluid transfer delivery system having a mobile dispense to transfers liquid from a chemical delivery vessel to a chemical-receiving device, e.g., a dry cleaning machine, with return flow of vapor therefrom to the delivery vessel. A first passage selectively connects the delivery vessel to the liquid-receiving device. Liquid is only then pumped to the liquid-receiving device. A second passage connects the receiving device to the delivery vessel for a vapor return flow. A chamber of the apparatus has a filling valve to receive a filling adapter to deliver liquid. Associated with the filling valve is a relief valve mechanism providing continuous, uninterrupted liquid flow at an increased liquid flow rate through the first passage, inhibiting backflow of liquid through the second passage for continuous, uninterrupted vapor flow from the liquid-receiving device while liquid is being received by that device.