0.4" / 10mm Straw Cover: These straw caps are suitable for a wide range of straws with outer diameters between 8 to 10mm. The inner diameter of the straw toppers is 0.4 inches (10mm), making them compatible with Stanley 40 oz tumbler straws and most 0.4-inch diameter straws. They offer a secure fit, ensuring they won't easily come off. Please check your straw's diameter before purchase. Perfect Gift Choice: This set of 9 straw covers not only serves as charming straw decorations but also offers dust and splash protection. With their unique patterns, they make excellent gifts for birthdays, straw-themed parties, and outdoor activities that will surely dazzle your friends Safe and Durable Material: Crafted from food-grade silicone, these straw covers are durable, reusable, and completely safe. Their exquisite workmanship ensures clear, long-lasting patterns. You can easily clean them by hand or in the dishwasher. Ease of Use: Simply thread the straw through the ring, and the straw cover securely attaches to the straw. When in use, the straw stopper hangs on the straw, preventing loss and maintaining the cleanliness and hygiene of the straw. Discover even more creative and fun STANLEY CUP series products that ignite life's excitement, all brought to you by AINEEDY 8 Pcs Bling Straw Cover for Stanley 30&40 oz Tumbler Cups, 0.4 in / 10mm Wide Cute Silicone Straw Topper Tips Lids Protectors for Compatible with Stanley Cup Straws Accessories - Jewelry