These are great for the bathtub, better than any bariatric stool, chair I've used.  I had hip replacement surgery 11/2022 and was wanting something to sit on that was roomy enough and would hold my 350 pound body without collapsing.  I bought these in a set of 2, so I have one as a backup.  So far it's not rusting.  It has holes in the seat for drainage.  I'm so glad I got these.  I used to use a regular metal folding chair and that started to rust and I was worried it would break and cut me badly.

A year later, I’m status post left knee replacement and the same chair is holding up well.  No rusting that I can see.  My only complaint is the seat is kind of low for me.  I wish the seat was a couple of inches higher.