I got this a few years back when I got the new mattress. While I was long overdue for replacing the old mattress, what sealed the deal and made it mandatory was a bed bug infestation. This cover purportedly is bug proof, but also waterproof. And that's been put to the test a few times.
https://www.amazon.com/gp/product/B08C4HTB2V/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&psc=1
And yes, it's PUL.