S'well Vacuum Insulated Stainless Steel Water Bottle, 17 oz, Mercury Our bottles feature triple-walled construction, designed to keep beverages cold for 24 hours or hot for 12 Our bottles are made from premium grade, BPA-free 18/8 stainless steel. Condensation-free, the exterior will remain dry. 17oz emulates a standard size water bottle, and is perfect for staying hydrated at the gym or on-the-go. Authentic S'well products direct from the manufacturer are only shipped and sold from Amazon.com.