My dad had one of those in his shed, I don't think he rated it very highly because he binned the saw and gave me the case, which I still have but have yet to find a decent use for. I know it was in a set of tools my elder brother bought at a farm sale, which turned out to be ex MOD, and were originally part of the equipment of a Bren Gun Carrier, the operators manual for which I still have somewhere.
Dave