Heat Retention: Double walled Vacuum insulated technology keeps beverages hot or cold longer, Inner copper coating for better temperature retention with thermoseal technology, Handle with Care | Has a special carabiner loop lock for travel, gymming, trekking and daily use. | This reusable water bottle is made from 304 Grade stainless steel, leak proof, durable, unbreakable, rust proof, Double Wall Steel Water Bottle with inside outside stainless steel made of grade 304, which is odour free and 100% food grade | It is simple to use and easy to clean with inner and outer steel that is convenient to wash. This bottle is easy to clean and maintain, Use a mild detergent or dish wash liquid and clean on the inside with a bottle brush.