What is a 'primary school'? Is that like a prep school for oiks?
The 88 set 'pressel switch' certainly had a rather dubious look about it, I agree:
Total thread drift - why did the 88 set supplied to many school CCFs have an interference pin fitted to stop selections of Channels A & B?
Once went into the local town with a chum to collect the Sten gun blank-firing barrel which had been repaired at a local gunsmith. We had to take the gun along as well to check the fit. The look on the faces of people when my chum fished a Sten gun out of his briefcase was priceless!