Gas meter (Twickenham TW1 (St Margarets))

For reasons too complicated to go into, it was installed by the plumbing company that put in central heating in what used to be a separate flat in our house, but never registered with our energy supplier or used for billing because there was already a meter for billing the gas supply to the house, and now it has been uninstalled because it wasn’t being used.
I can’t imagine who’d want it, but I thought I’d give it a go.