Unbreakable double walled stainless steel interior and exterior. Leak proof and spill resistant. Thermos® Nissan Leak Proof Tumbler: Fits most automobile drink holders, with integrated carabiner. Stays hot for up to 4 hours, cold for 8.|Thermos® Nissan Stainless Tumbler: Slim body allows for a comfortable hold and fits most automobile drink holders. Stays hot for up to 3 hours, cold for 6.