Description 【Safe Material】The coffee cup is made of double-layered 304 stainless steel with vacuum insulation. It effectively keeps beverages cold for 6-8 hours and hot for 5-6 hours. The lid is made from environmentally friendly materials, ensuring no unpleasant odors in your drinks. 【Leak-Proof Flip Lid】The tight-fitting flip lid design offers superior leak-proof functionality compared to other open designs. The lid, equipped with a silicone ring, securely fastens to the cup by twisting, eliminating liquid spills more effectively than traditional press-on lids. .