Not sure of manufacture date,im trying to findout who made them,looks like a C type trolley,theirs traces of RAF blue on it,it had been half burried in grass at a caravan park on lincs coast for sum years which has seized the towarm & swivel peice (now unseized),the swivel housings on the end of the axles are still seized but im working on it!! i cut some addon steel off it,steam cleaned it off then sprayed it with oil,im trying not to get too sidetracked with it at mo as i want to get my bowser chassis done 1st but i carnt resist doing little bits at it,i need to remake the tiebar to steer it as its long gone but i have a friend with a museum nr lincs whos got one on a trolley i can take measurements © &theirs the brakes missing but i doubt i would find any to go on it.