Heat Retention: Double walled Vacuum insulated technology keeps beverages hot or cold for 24 hours Inner copper coating for better temperature retention with thermoseal technology, Handle with Care This reusable water bottle is made from 304 Grade stainless steel, leak proof, durable, unbreakable, rust proof, Single Wall Steel Water Bottle with inside outside stainless steel made of grade 304, which is odour free and 100% food grade Trendy design and a wide array of colours.