I got these for a 16oz Fifty/Fifty bottle (16oz isn't listed in the description) and it worked great.
My travel mug started dribbling, so I ordered the replacements rings—and viola! It's leak-proof again!
Absolutely necessary to be able to use thee bottles
I took a chance. they are cheap. shipping costs as much as the product. they dont fit my coffee mug. I have to wait until replacement lids are in stock. No idea why I have to buy a new lid when all it needs is the seal ring.
JOIN THE FIFTY/FIFTY COMMUNITY!