I'm trying to figure out the best way to attach an MK Egatube Tee Box to
a wall:

https://www.mkelectric.com/en-gb/Pro...ges/2ECR5.aspx

But I'm a bit baffled about the best way to do it (and Google is not
helping).

The catalogue refers to "swivel lugs" but doesn't explain what they are,
or how to use them.

On the back of the box, there are a couple of holes (extending from the
lid screws) which I can imagine would be part of a mounting system...
but nothing in the catalogue looks like it would be used for this.

i.e. Like the fixing bracket for Wiska boxes:
https://www.tlc-direct.co.uk/Products/WKSMB.html

Is there a mystery part that I'm missing?

Thanks for reading.