How interesting, there were several attempts in the early to mid part of the war to make light weight machines could it be something to do with that?
After the war aluminium was available in such large quantities that companies such as Landrover and VP sidecars to name but two were trying to use the stuff up, but of course the flat glass DU42 had gone out of favour by then??
Could they be prewar for sporting use???
I will take one for my lightweight B30 if you have one left