What the ad on eBay also fails to inform you of is that this tap, in particular, is also a direct switch-out for the Left, Right and Indeterminant Blinker fluid tanks on many Spagthorpe Motorcycles that were developed between 1936 and 1952.
Few of these taps ever make it to the open market, hence the unusually high price listing.
" Don't worry, if it ain't broke, I'll fix it for ya"