Product Size. Illuminated Silicone Straw Cover Accessory for Stanley 30 and 40 oz, 10 mm/04 inch Stanley Mugs, fits all 9-10 mm straws, dustproof reusable water bottle protector cover. Silicone straw cover cap for stanley cup lids are small and easy to carry around on a daily basis, especially for outdoor activities, walks and camping. Safe Material Made of high quality food grade material, BPA free, odorless, durable, reusable, hand and machine washable. Good Protection Our stanley straw can perfectly protect your straw. It effectively prevents dust and splashes. The stanley straw cover can be fixed on the straw or hung on the side of the straw after opening the cover. Prevent loss, easy to use and keep your straw clean! Durable and versatile Reusable Cute stanley accessories for 0.4 inch/10 mm straw toppers come in a variety of shape combinations for you to choose from. They are all very popular. I want everything. The water seems to taste better when you drink from it.