I have compared different offers specially for F-couplings before ordering and decided to go for this. Reason: The picture shows a brand with a round Complete thread. Was supplied by premiumstore24 + a Noname product with "half thread" that is, the threaded connections are not round but on the sides just as these parts: ; RefRID = 00GWGJ10833A7G3NCHGJ Through the flat areas that have no contact to the threaded plug, a gap through which moisture can penetrate. Not nice, because I want to use the links in the attic.