There you go!
Only needs a few squeezes. I'm sure there must be a non-return valve but I wouldn't think it could be relied upon to make a good enough seal if you were to leave the car for a few weeks.
Friend in the Netherlands leaves his in place all the time and he's never mentioned it leaking, it seems to be a popular fit there.
However I still prefer the electric pump fitted just in front of the furl tank about 5 years ago , although I recently had the fuel hoses to and from it changed, as they were leaking .
Brian
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