Contigo Autoseal West Loop 1.0 Stainless Steel Travel Mug with Open-Access Lid, White 16 oz Patented AUTOSEAL lid is 100% leak-proof and 100% spill-proof. Vacuum-insulated technology keeps beverages hot for 4 hours, and cold for 12 hours. Contoured body makes this travel mug easy to hold and easy on the eyes. Constructed with a double wall and stainless steel inside and out for maximum travel mug performance. 100% FDA-approved, BPA-free materials.