This 30oz travel mug is made with high-grade 304 Food Grade Stainless Steel, anti-rust and lead free, unbreakable and stands up to heavy use through every season. Clear press-on lid helps you see what's inside. This stainless steel tumbler keep your on-the-go beverages hot for three hours or cold for nine hours, perfect for the office, road trips, camping and hiking, sporting active, picnics.