Here are some do-dads I saved a pic of from a similar
thread awhile back... if I bookmarked it also, I can't find it at the moment. But I had saved some notes in the file name lol, such as that they are for capping stuff like glue, chalk, I dunno. And are apparently available at hardware stores. I could swear ppl on that
thread were referring to them as "rat rubbers" hehe but last time I searched on that it didn't come up... Anyway they look rather useful I think.
(ecoflowerpower -- people are looking for various rubber or silicone thingies to re-cap juiced cartos or atty carts, when for various reasons they don't have the original caps anymore.)