The wine tumbler is made of good quality stainless steel, BPA Free, Lead Free, durable and unbreakable. Its double-wall vacuum insulation technology keeps your beverages fresh whether it is hot or cold drink inside. Set off on your refreshing picnic, hiking, camping, home or office with your water, drinks, wine or cocktail icy-cold for 7 hours or your coffee and tea scalding-hot for over 3 hours!