From what i understand it was something called a 'duffus type' from Bethel Rhodes.
But the make surely doesnt bear a difference, though i will say i have handled a Bethel Rhodes and it was pure crap! The wire was very, very soft and , apparently, needs tuning everytime it goes in the ground. Modern BR are not a patch on Flatpack, but i'm speaking as someone inexperienced in such matters, but anyone can tell cheap build quality.