Our glass tumbler come with a screw lid and silicone ring, making it airtight and leak-resistant, which saves you from accidental spillage or overturns. The merchandise made of thickened glass, make the cup stronger to support higher and lower temperature. Double wall to prevent scald BPA-free, odor-free and pollution-free. This bottle is lightweight in design which makes it quite easy to carry around. This characteristic also makes this tumbler/sipper suitable for School, Travel, Picnic, home, everyday use, etc