I went out for the day and came back to some very strange ideas on this object...I rather liked submersible window, it does have that look, doesn't it? Also pretty useful as a spitoon, but I don't think I'd fancy it used for piles to be honest...
Well, bah humbug. Someone's got it right, although they've got the wrong company.
Well done Adam, although it's cheating a bit as you knew and didn't guess.
It IS an airfield landing light and it's marked 'Holophane', I think that gives Adam double-points! :hiclp:
So, if Davidsons didn't make this particular
item, then who did?