Whether you are on a camping trip or working in the office, this mug will provide a clean, fresh taste! The sturdy wide-mouth mug is made of high-grade stainless steel and won’t rust or rupture. The materials used in the thermos are environmentally and BPA free. A double-layer vacuum insulation keeps your beverage cold for 8 hours or hot for 4 hours. Perfect for school, work, travel and camping.