Material Safety 316 stainless steel: medical grade material, corrosion resistance is better than 304 stainless steel, suitable for storing coffee, tea and other acidic/alkaline liquids, no risk of heavy metal precipitation.Inner liner process: seamless inner liner design, reduce dirt residue, easy to clean. Thermal insulation performance Long-lasting heat preservation: double-layer vacuum structure, 6 hours of heat preservation above 60, 12 hours of cold preservation below 10 (specific data need to refer to the brand lab report). Sealing: silicone seal ring + threaded cup mouth, leak-proof design, suitable for car/backpack carrying. Usage Scenario Daily commuting: thermal insulation performance to meet the needs of drinking water throughout the day. Outdoor sports: leak-proof design + drop-resistant material, suitable for hiking, cycling and other scenarios.