I was given this by someone else and then another kind person helped me by supplying a colour of the instructions and some advice.
I have kept the gasket sealing ring as a spare for my own similar pressure cooker. And I couldn't make the little ? "safety plug" move up and down as it should. So it probably should be used just as a large heavy flat-based pan perhaps, rather than a pressure cooker, unless you can solve this.
Collection from Dodleston but I anticipate taking several days before I can respond to responses.
Thank you, Nicola