This 'thing' was already in our portfolio years before I arrived in the 80s. They're expensiver than sin. Usually maybe a dozen were ordered every other year and, because documentation was not an immediate cash flow positive, every production run was akin to making a prototype. It's the kind of product where with every customer order you hope it's the last one and it finally dies. But it doesn't. The customer outfit might change slightly but they're always from the same group of companies, involved in things that go... BOOM. Hope I didn't startle you. Recently, I caved and optimized the crap out of the documentation because I was fed up with encountering the same questions every time these are ordered. Death by a thousand paper cuts, if you know what I mean. Specced out torque measurements and tolerances, redid the whole text of every production step (within reason), made actual sensible parameters for final control where good CpK can be achieved, based on customer's and supplier's spec. Corrected an old error that regularly lead to unpredictable numbers of failures in final inspection. (Not that I expect the customer would notice any of that, the thing is at worst unnecessary, at best not critical but I've nothing left but my pride :) ) Wouldn't you know it, more orders come in. The last run was the first one that went through production without any stress factors. Makes sense that I was fired. Also tells you something about innovation in the German military.