Copper lined, vacuum-insulated liner maintains 8X optimal drinking temperatures 18-8 Stainless Steel dual wall construction Lead-free vacuum seal Inspired by the award-winning 3-in-1 Insulator (SL233SS), the Stacker is designed to hold two 12 oz cans at the same time Self-contained unit transitions between poured drink insulated tumbler and two 12 oz can cooler Twist top rubberized ring to hold two standard 12 oz cans Black screw-on, flip top lid with handle available for additional cost / Water Bottle Lid (SCTP13) upgrade available for additional cost; turns the unit into a 27 oz water bottle Sweat-free design 1-year limited warranty Patent pending Features 2 attachments: clear screw-on, thumb-slide lid and a black can ring