These flasks are equipped with several different types of heads, by example the Boche a Paris type, the Dixon-patent type, the type of the Hick and Weatherwax Patent, heads with cross spring charger ..... A fascinating collection!
I am wondering, if these flask heads have been industrially made and then been used by craftsmen for their shop-made flasks?
I guess, that the flasks with a knee action charger (like Riling 1390 and 1394) are older than the other flasks? Am I right with this thinking? I have never seen a flask with a knee action charger for an affordable price.