Super high quality. Positive shut-off when disconnected. The male half has a bar across the opening which pushes the valve open in the female side when connected. Not sure just any male fitting will work because of the shape. I bought 2 so I would have a female end on both propane generators, allowing the use of gasoline once the propane hose is disconnected. The female closes air tight without the male connected. I put the male on my supply hose so I can use it on either generator. The supply hose is shut on and off by a control handle on the propane piping.