Renee, from Friday’s glue/tape cartridge question, also asked about bottle cap liners.

Again, I wasn’t sure what she meant but thankfully she included a picture —>

I don’t see them used that much over here (or at least not in the things I buy) but I think they’re basically a washer to help the seal between the cap and the top of the bottle (??).

I think I’ve seen some waxed card ones (which usually get soggy so are good for little else after their intended task) but these ones that Renee are asking about look to be circles of plastic.

In searching for more information about them, I found this very cool bowl made out of 100 of them and I guess they could be used for oversizedtiddlywinks too. But what else can be done with them?

(If you’re interested in other bottle cap related stuff - we’ve covered plastic screw-tops and metal caps elsewhere on the site.)