This is a single barrel system that can easily be expanded. I have used an expandable section of downspout above the diverter in order fine tune the water level in the barrel. The diverter looks a little low but there is an internal overflow in the barrel that the water must stay below. The water level in barrel will not go above the top of rain diverter. The filling hose has no valve and is hung on the fence above the level of the rain barrel.
Both the diverter and the barrel have standard male hose connections. I have used one small extension hose (M - F), one washing machine hose (F - F), one tee connector ( M - M - F ) and a 50' hose (M - F).