Compatible with Stanley 40 OZ tumbler straw and most straws in diameter 0.4 inch(10mm). Made of silicone, these silicone straw covers are durable, reusable, and can be cleaned by hand or in the dishwasher. Not only can it be decorated but also can increase children’s habit of drinking more water. It is airtight and sealed, dustproof and splashproof, especially suitable for outdoor activities, and can effectively block dust and other foreign objects from entering. This portable straw lid kit is small and easy to carry, making it perfect for outdoor activities like walking, camping, and hiking. Support Pantone color customization. Measuring 1.3*1.3 inches, this custom silicone straw cover cap for stanley cup 6-10mm. Usage Scenarios: Office supplies, school stationery, corporate promotions, trade show giveaways. Tailored branding: Supports logo imprint and design personalization. Product Highlights: BPA-free, leak-proof, travel-friendly.