[Straw Cover: Suitable for the straws with a diameter of 0.4" (10 mm) Exclusively for 2.0 Tumblers: Designed to be compatible only with Stanley Cup 2.0 40 oz 30 oz and 20 oz tumblers Premium Material: Made of premium silicone durable reusable and easy to wash by hand dishwasher Protects Your Cup: The straw topper prevents spills the straw fix stoppers stop spills and secure the straw and the lid spill plug stops leaks while making it easy to drink Purchasing one you can get: 1× Straw Cover 1× Round Leak Stopper 1× Square Spill Stopper]