You want to make sure you're using PYREX, not pyrex. They're different![1]

[1]: https://www.allrecipes.com/article/what-is-the-difference-be...

The biggest difference is that the latter is the only one you'll find in stores, at least in north america.

Unreal that this very misleading branding was allowed to continue.

I somehow ran across this trivia twice today. It stings; Pyrex was a brand I still trusted.

The other thread mentioned that they license rights to use "pyrex" (vs "Pyrex") to pretty much anyone, but the capital-P brand should still be the OG company. Maybe that was relevant in your case.

At this point I don't trust it if it doesn't at least explictly claim to be made with borosilicates. There are such suspicious items for sale on Amazon and I trust them more than "pyrex."

Do you know if there is another borosilicate glass cookware company now?

I don't understand why anyone would do this even with real borosilicate glass. It is unreasonable to expect glass to survive with something massive and hot on one side and something massive and cold on the other side. Even flawless pyrex will break with temperature differentials above 300F.

Real Pyrex really ought to survive a 300F (150C) temperature difference.

How high do you believe? What do you think the temperature coefficient of expansion is for pyrex bakeware?