Technical What are these?

[JonPiz]

Found these under the car and have no idea what they are

 

[bugsymike]

Found these under the car and have no idea what they are View attachment 469540

I would guess bracing supports for seat belt mounts.

 

[JonPiz]

I would guess bracing supports for seat belt mounts.

It’s strange as the whole car is under sealed yet these are bare metal

 

[bugsymike]

It’s strange as the whole car is under sealed yet these are bare metal

Do they look like they accept seat belt size bolts?
If not they appear to be some form of strengthening plate for thin metal.