These are the jars they use for it, you can use any jar however they've been doing this for a thousand+ years and figured out this is the best shape.
Older jars were made from ceramic rather than glass but the glass versions are way more popular today.
I've been meaning to buy a couple but really any large jar will work it's just keeping the bugs out while letting gasses escape so it doesn't explode or suffocate.
https://cdn.nostrcheck.me/cdf73fa34146549298cb2127638f92a0035bdb1287eb2cb57b4574198db9a4b2.webp