What are these brackets for?

[Last triumph]

Not my car, (mine has them) but I'm really intrigued as to what the function / purpose of those two rectangular steel brackets are that are immediately inboard of the tail pipes, directly behind the bumper.
They've screwed into the rear crash bar with just a pair of sheet metal screws and I cannot fathom what they do?

 

[Oneball]

1980 Corvette: Recall: Towing Bracket Installation

1980 Corvette: Product Campaign: Towing Bracket Installation - General Motors has determined that some 1980 Corvettes may experience front or rear bumper cover damage during vehicle lift in preparation for towing.

www.corvetteactioncenter.com

 

[Last triumph]

1980 Corvette: Recall: Towing Bracket Installation

1980 Corvette: Product Campaign: Towing Bracket Installation - General Motors has determined that some 1980 Corvettes may experience front or rear bumper cover damage during vehicle lift in preparation for towing.

www.corvetteactioncenter.com

Brilliant, thanks.