I bought this to extend some RCA speaker wires with another pair of wires I had lying around. It serves exactly that purpose, and I have not noticed any quality degradation by using these to connect them.I do have to mention though, the picture is misleading. These are actually two separate couplers, although the picture makes it seem like it is on piece. For me, this is no big deal, and actually works better in my opinion, but be aware of that.