I get most of my stuff in auctions, old car stuff & preferably old ford stuff. But those running estate sales know zilch & mish-mash inventories. So I end up with unknown stuff like this, or one time it was a float level sight glass for stromberg that almost went to brass scrap. This could be a manual lubricator for specialty tool or acessory, fuel injection for a whizzer bike... So somebody may have seen this somewhere, cast alum tank has brass filler cap & pump plunger, handlebar like mount & aparently dual outlet holes in the bottom.