Go "green" by packing drinks in your thermal insulated bottles, instead of disposable bottles. Zojirushi utilizes high quality vacuum insulation to keep beverages hot or cold for up to 6 hours. Lightweight, durable and economical. Unbreakable all stainless steel construction with excellent heat retention. Extra wide mouth and easy-to-clean nonstick interior. Tight fitted lid keeps beverages hotter or colder than other travel mugs.