\is this a mk1 n1 or a 2 inch disharger
i know the 2.5 inch burns was obsolete by ww2 and
replaced by the MK1 Number 1
is that the 2 in discharger
also when did the MK5 get introduced some say ww2 some say after
its not on wiki and google searches are just confusing at the moment the uk has only he n1 mk1
is there that much difference between the mark 1 2 3