could be the jacking piont support, located just above the half circle cut out thats in the bottom of the sill, one at the front one at the rear

Hello fellow Datsun owners. I have a question about the sill panel on my 1200 coupe. Iv been cutting rust out of the floor and sill panel and i have noticed these metal things? with a large hole through the middle of it, located under the sill. There is one at the front and rear of each panel. Does any one know what these things are for, I felt like cutting them off because they look useless but i thought id ask the question first.