Spill-Proof Silicone Accessory Set for Stanley Cups - Includes Straw Covers, Round and Square Leak Stoppers - Anti-Dust Tumbler Accessories

Works better than I thought. Sometimes too good. You can't use the bigger piece and drink from the cup at the same time. If you are traveling you can use it but remove it to drink from it. It is leak proof. Great design. Easy to clean and fits perfectly.

My daughter and I were disappointed with how much the Stanley cups leak. These nicely fit stoppers truly helps! My daughters 40oz doesn't leak at all, my 30 oz does maybe a driplet. Honestly, I'm nervous of tipping it over like my daughter does hers all willy nilly. I like the simplicity of the rubber and the top stopper seems like it can handle alot of putting and pulling off. Great product, great price.

Best thing since sliced bread! 👍🏼 Works great!

The straw insert works well to eliminate the gap for water to spill around the straw. The round insert under the cap doesn’t stay on and it’s tough to drink out of with the air flow restricted. I tried putting a few holes in it but it still falls off into my mug.

The Spill-Proof Silicone Accessory Set for Stanley Cups is a handy addition that helps prevent leaks and spills while on the go. Made from flexible, durable silicone, the set includes covers and seals that fit snugly on Stanley tumblers, enhancing their usability and keeping drinks secure. Perfect for travel, outdoor activities, or everyday use, this accessory set adds peace of mind and convenience to your hydration routine.

Parts fit on pretty well at installation, but don’t stay in place. Center “under lid” part keeps falling in drink. The part that goes in with the straw doesn’t stay in place well if you ever have to move the straw around. If you just need a basic straw topper those were ok.

These cups leak a lot if turned over. This company has made a great product , with this installed in your Stanley cup there's no more leaking.

These are useful and prevent leaking. I'm paranoid of having an uncovered straw open to the elements so I had to have a straw cover. The bit that goes in the hole for the straw stops leaking really well, not completely but a few drops is fine. The other bit that goes on the inside of the lid seems pointless, works fine without it.