TQRR 4 Pcs Silicone Spill Proof Stopper Compatible with Stanley 40/30 oz Quencher H2.0 Tumbler with Handle Leak Stopper for Stanley Cup Accessories Including 4 Straw Cover Cap, 4 Round Leak Stopper

Excelente, dice q es para 30/40 oz pero se los puse a uno de 20 y le quedó perfectamente, te olvidas de los derrames de líquidos y evitas q por el popote le caiga alguna basurita o bicho a tu bebida.

We use this on the Stanley tumblers and it works wonderfully: no spilling. I’ve tested it by filling up each container and held them upside down for 30 seconds…not a drop.

Recomendable

Bought this for Christmas for my daughter. Works great! No leaks!

While they do help with liquids leaking from your stainless cups thru the lid, they aren’t 100% leakproof but I would say 98-99% effective. Still a great product and necessary for the cup lids