Wire through mechanical lug

[PaulEd]

I want to know if this is legal. I’ve heard that you can’t run a wire, THHN, or similar directly through a mechanical lug as it’s not rated for it? Should this slug be an open type lug or is it OK to run this wire through the mechanical lug like this?

 

[PaulEd]

I can’t attach a photo for some reason

 

[ptonsparky]

I've done it before, doesn't mean it's correct. Depends on what you want to do.
Lay in lugs, common on the larger grounding bushings, absolutely. One conductor bonds all the raceways together and to the enclosure.

I use Screen Snip for quick attachments.