Delco-Light 7B12
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wasapparently originally intended to charge batteries in a WWII mobile
workshop. The vertical pipe which I had assumed was some latter day
addition, is in fact correct and should house a dip stick (rather than a
plastic bottle stopper!).
Never quite sure why I aquired this less than inspiring unit and it has been
on my mental transfer list for some time, perhaps I'll feel a little more
positively disposed towards it now I know a small part of its history.