What name or type of socket is this please

Hi all, this 110 volt gen set I have just acquired has this socket fitted in  what I think would be called a control box, if this term is incorrect sorry but know nothing about electric part names,  what I would like to know is what the correct name/term this socket would be called so I can search for the part that will go into it, I E  the plug.  

Looks like a Niphan socket - https://www.lpa-group.com/product/niphan-flange-socket/?com=LPA%20Transport%20+

Thanks Stuart, its not as you say, it is made by a company called LEWDEN who a friend of mine tells me are still in business, have messaged them now awaiting an answer.

Don,
According to the chap at the Electric Centre in Darlington their branch in Sunderland should have plugs that fit. Unfortunately they don't have ones to fit Niphan sockets, thanks Stuart I'll get in touch with Niphan direct

Looks more like a 3-phase socket to me. Lewden did these years ago with weather proof screw fittings like the one you have.
Today I think the Lewden plugs are all bayonet fittings, and they don't do the 5A size.

There is a new one on ebay:
https://www.ebay.co.uk/itm/174764058568?epid=28018753767&hash=item28b0bfe7c8:g:L60AAOSwoMFd63h4
But you won't like the price.

There is also this used one, but you will need to check the sizes you require with the seller first, particularly the diameter of the screw ring, pin centres, etc.
https://www.ebay.co.uk/itm/293053583381?hash=item443b5ad015:g:F1YAAOSwuXxct5Ww

You will find that Niphan plugs are pretty expensive. But it is not a Niphan.

As it is probably not original, you could of course replace it with something cheaper and easier to find  

Well you are correct about that  price Blue Cat, the whole unit I have only cost a few bob more than that asking amount, as something else is been powered I will just forget using this socket, had a mate use his test equipment today and all is good to go safely, am always wary  with this lecy stuff as cannot see it.

Thanks for heads up though,  Don