http://www.fetware.com/locking-waist-plastic-pants-p-112.html
https://www.thedottydiapercompany.co.uk/product/locking-plastic-pants/
https://www.amazon.com/Haian-Pull-Locking-Plastic-Pants/dp/B07QYRDLBH
I actually own two such items, which I’ve owned for a number of years. One of them I believe is Fetware, the other one I believe is a manufacturer that’s not around anymore.
I’m in a state of near-panic because so many of the small, “boutique” manufacturers seem to be exiting this market.
I had always wanted to ask if they could make me a custom, “chastity belt” version of the product with lockable chains around to leg openings as well as at the waist. I’m afraid I might never be able to do that if the much larger Chinese manufacturer Haian is the only one remaining.