[Perfect Fit] The 30oz replacement tumbler lid has an inner diameter of 1.94 inches and an outer diameter of 2.1 inches, perfect fit, works with 30oz Yeti Rambler, 14oz mug and 35oz sippy cup, old fashioned cup and most other tumbler or mug designs, compatible with YETI rambler, Ozark Trail tumbler, old fashioned cup or other mugs and 30oz tumbler. (Tip: This lid is not compatible with rambler bottle or water bottle or travel mug with fortress lid.)<br> [Safe and Premium Material] Our 30oz YETI replacement lid is made of premium quality ABS plastic, BPA free, which is environmentally friendly, shatterproof, sturdy and durable. Equipped with a food grade rubber lid ring, the lid's button is tight for your convenience. Dishwasher safe, but please avoid using in the microwave. <br> [Lid with Strong Slide] Each spill-proof tumbler lid comes with a slider replacement for YETI. No need to worry about losing the slider, or spilling liquids while driving or traveling. The slider switches smoothly and is easy to remove and wash. (The lid slider prevents spills, but is not leak-proof.) The drinking hole can be cut directly or use a straw, no need to touch your nose when drinking. The 30-ounce Yeti lid size makes it easier to grab/remove the lid and clean the entire lid, overall, this product is easy to use and worth the money. [Splash-Proof and Heat-Insulated] The replacement lid seals securely to prevent leaks. The slider has a built-in black silicone O-ring that wraps tightly around the edge of the lid and fits snugly around the cup to prevent leaks. The thick lid keeps your drinks warmer, cooler, or hotter for most of the day. The container lid is tight and fixed stably, so there will be no leaks when drinking, and it keeps your drinks at the ideal temperature (warm/cold) for a long time. [Easy to Clean] These tumbler lids are crystal clear, and the transparent lid allows you to see how much of your drink is left without opening the lid. So you can decide if you need to refill. The black closure can be easily removed and the lid can then be rinsed under running water.<br>