Fuel Tap or Fuel Valve for Vespa LX 150, LXV 150, S 150 and GT 200 with carburetor AND electric fuel pump. 

These are the last ones made before the switch to fuel injection. If the part you are replacing looks like this, and there is a single fuel line coming out of it, this is the right part. If there are two rubber hoses coming out of the part at the bottom of your fuel tank, this is the wrong part. 

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