These Leak Stoppers are designed to be compatible with THERMOS FUNTAINER 16 Ounce Stainless Steel Bottles. They provide a secure seal to prevent leaks, ensuring your beverages stay contained within the bottle. Made from durable materials, these stoppers offer a reliable solution for maintaining the integrity of your THERMOS bottles. Simply insert them into the bottle opening to create an airtight seal, preventing spills and messes. With their compact size, these Leak Stoppers are easy to store and carry, making them a convenient accessory for your on-the-go hydration needs. Keep your drinks fresh and your surroundings dry with these practical Leak Stoppers.