【Perfectly Compatible】 Our straw caps have a diameter of 10mm (0.4in) and are designed to be perfectly compatible with the Stanley 40 oz/30 oz tumbler with handle, as well as the simple modern 40 oz tumbler with straw. They also fit all large-diameter long straws with a diameter of 9-11mm, but please confirm the size of your straw before purchasing the straw cover cap.【Food Grade Material】: Made of food grade silicone, these straw covers are durable, reusable, and easy to clean by hand or in the dishwasher. They're airtight and sealed, dustproof and splashproof, making them perfect for outdoor activities. Plus, they can help encourage children to drink more water.【Cute Design and Practical】: These straw toppers are not only stylish, but practical too. They effectively block dust and other foreign objects from entering your drink, without harming your body. And they look cute too!【Easy to Carry】: This portable straw lid kit is small and easy to carry, making it perfect for outdoor activities like walking, camping, and hiking.【Satisfied Service】: We value your satisfaction above all else. If you have any questions or concerns, please don't hesitate to contact us. We are committed to resolving any issues you may have within 24 hours. Please note that this product does not include a straw.