However, what arrives is somewhat different!
For a start, it is not "Mills" anything (I assume Mills is the manufacturer), It claims to be an "Eaglehawk Product". It also has "C.E." (yes that is not a CE mark), and a "Patented Product". Hmm.
This is what it actually looks like when it arrives :-
We took it apart, and it looks like this :-
Note the way the plug is crimped - looks to have been done with a screwdriver blade and not a crimp tool.
We won't be using these, or anything else from this supplier :-)