Engel Tumbler - Stainless Steel Vacuum Insulated with Lid - 30oz Patented double-wall vacuum insulation technology, holds ice up to 2X longer than plastic tumblers. Keeps ice up to 2X longer than plastic tumblers and is designed for maximum ice retention and heat retention for hot drinks. Made of durable kitchen-grade 18/8 stainless steel. Use for both hot and cold liquids without burning or freezing your hands. We love this size for summer beverages. Includes unique leak proof lid and non-skid base. Fits most built in cup holders and boats, cars and trucks.