RTIC 20 Oz Stainless Steel Tumblers - SET OF 2 20oz. RTIC Tumblers are stainless steel, double wall vacuum insulated. Keeps Ice Longer - Holds ice for up to 24 hours. Also keeps beverages hot longer. No Sweat Exterior - The outside stays dry. No need for a coaster. 18/8 Stainless Steel - Strong stainless steel construction Easy Grip Base - Taller base ensures a better grip.