- Perfect Fit: This 30 oz replacement tumbler lid features a 3.94-inch inner diameter and 4.1-inch outer diameter, ensuring compatibility with 30 oz YETI Rambler, 14 oz Mug, 35 oz Straw Mug, and Old Style tumblers, as well as most similar glass or mug designs. (Note: Not compatible with YETI rambler bottles, jugs, or travel mugs with the stronghold lid.) - Safe and Durable Material: Crafted from high-quality ABS plastic, this lid is BPA-free, environmentally friendly, shatter-resistant, and durable. It includes a food-grade rubber lid ring for a secure fit. Safe for dishwasher cleaning; avoid microwave use. - Innovative Magnetic Slider: Each lid comes with a magnetic slider that prevents spills while driving or traveling. The slider operates smoothly and is easy to remove for cleaning. Note: While the slider helps prevent spills, it is not leak-proof. The drinking hole allows for direct sipping or straw use without touching your nose. - Splashproof and Insulated: The lid features a built-in silicone O-ring that tightly seals the rim of the cup to prevent leaks. The design maintains your beverage's temperature, keeping drinks hot or cold for hours while ensuring a secure fit during use. - Easy to Clean: The crystal-clear lid lets you monitor your drink levels without opening the lid. The magnetic closure is easily removable for quick rinsing under running water. Use Scenarios: - Perfect for outdoor activities like camping or hiking, where a reliable and spill-proof lid is essential. - Ideal for daily commutes, ensuring your drink stays secure and at the right temperature. - Great for road trips or travel, providing peace of mind against spills while you enjoy your favorite beverage on the go.