It's clear enough to me, RM--but only because I know a bit about service pressure, proof pressure, etc. But I'm a writer and tend to be a stickler about clarity of language, and the language on that box is most definitely NOT clear as written. It gives the reader the impression that 850 bar is the service pressure of a gun marked 3 tons, which would mean that such a gun was built to accept standard SAAMI loads--which it most definitely was not.