What is this attached to my fuel line?

Hello, today I have been trying to work out why I have a poor fuel supply and thought it was about time I found out what this thing is connected to my fuel lines, in case it could be causing any problems.

I assume it is something a previous owner added, can anyone shed any light? I assume I can get rid of it?

The brackets are attached to the front of the seat box and the nozzle (breather?) fits into a hole (as you can make out in the photo). One of the pipes has been sealed but appears to be leaking a bit of something?



Thanks

Potentially part of an old twin tank change over (but cant really tell from picture), alternatively could it be part of some sort of anti theft hidden fuel cut off?

Thanks for that, think you are correct. Just been doing a bit more research and it looks like the black thing with electrical connectors could be a fuel change over switch? Maybe someone was running red diesel? I'll get rid of it and fit new pipes just incase it is letting air in.