2- Pack of Spill Resistant Splash Proof Tritan Lid with Slider Replacement Lid for 30 oz Stainless Steel Tumblers - Fits YETI Rambler RTIC Perfectly

I don't know why no one make a lid for these tumblers that is actually waterproof. I have the RTIC 30 Oz. tumbler. As far as functionality goes, the lids are as described- Splash proof and spill resistant. It seems if I hold my cup straight upside down it doesn't leak at all, but when sideways it leaks quite a bit. The seal is very stiff around the lid so it stays on very tight. If you shake it violently, nothing comes out which is nice. From what I can tell, there are no lids for this product that are completely waterproof, but these lids seem pretty good.

I am very happy with this purchase as these of great quality although a little expensive, that is why I gave it 4 stars.

They fit really well and do not spill! They also have the slide option on top that you can fit a straw in!

While this lid may save the majority of your drink from a spill, it is by no means water tight.

Fit my knock off yeti perfectly. And it has a sliding stopper the one that came with the knock off had a whole so I like this one a lot! Not wearing my drink on my way to work

Fits the Yeti 30 oz without a problem. Works well for preventing splashes in the car on a bumpy road. I can close it and not have to worry about bugs getting in my drink when I'm outside.

I've had these for a couple of months and really want them to be spectacular every time I use them. Unfortunately, wanting and reality are not the same in this case. The sliding closure is SO loose I literally have to push it forward with my upper lip before I can take a drink. The slightest tip one way or another will open or close it making it prone to spillage. I would not buy again.

These lids fit well, probably better than the original ones that came with our stainless tumblers. I like the mouthpiece slide for a straw, too. They appear to be sturdy. I would certainly re-order.