2X Vacuum Insulation - Engineered with advanced double wall insulation technology. Holds Ice Frozen - For up to 72 hours. Far longer than any competitors Keeps It Hot - Works great for hot coffee and other hot beverages. Strong & Durable - Strongest available drinkware copper lined food grade 18/8 stainless steel. Wide Mouth Lid - BPA free lid for safety that is virtually indestructible.