What are these M10 holes for?

[BlackZR1]

Looking up at the bottom of my car just inboard of the front jacking points on both sides of car I see these 4 - M10 tapped holes on a 1" x 3" pattern. (See pic) Anyone know the purpose? Maybe a chassis stiffener mount for convertible cars?

I was thinking of making a couple of 1" thick 6" x 3" UHMW pads to mount there for better lifting / jack stand contact area.

Thanks,
Roger