I imagine people installing this stuff do not think about what they are doing. I can't comment on your particular model as I have a fifth wheel that they installed the black empty valve perpendicular to the side wall I-beam and it sits on the I-beam frame. No way to get to the two rear screws and nuts to the valve. I can't take it apart to put in new seals without redoing the whole sewer line.
I know this doesn't help you other than let you know, quality is not number one in the RV world.
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