We do regulate body armor though.
I wonder what the rationale behind this federal law is. Does wearing/purchasing armor indicate that you, convicted felon, are simply up to no good once again? Is it one of those "you don't need ~~privacy~~ armor if you don't have anything to hide" things?
[1] https://www.shotstop.net/resources-1/2020/9/8/is-it-legal-to...