Straw covers cap. It perfectly fits for 10mm large size straws such as Stanley 40 oz / 30 oz tumblers straws. Silicone straw covers. Made of food grade silicone, safe and durable, perfect for decorating your straw cup. Anti-dust, anti-fly and splashing proof. Straw cover. Creative cute cloud shape, which is adorable, lovely and decorative. Straw topper. Easy to clean, wash it with your hands or throw it into the dishwasher. Great Stanley Cup Accessories. Great novel gifts! Great for your friends or family.