Trying to ID aircraft relic – made by Ellis & Co (Birmingham) Ltd

Can anyone help ID a WW2 aircraft relic? It has a distinctive inspectors stamp – ECLB. This seems to stand for Ellis & Co (Birmingham) Ltd. It seems they may have been a sub-contractor to one of the larger aircraft firms. Can anyone supply more info on this firm and what they made during WW2 pls? An internet search suggests their peacetime activity may have been silversmiths.