Material: inner 304, outer 201 stainless steel. Heat preservation performance: 12-24 hours Style: Sports Style: handle Color: white, black, yellow, blue, pink. Capacity: 500ml Solid stainless steel with corrosion resistance is eco-friendly and durable for years of daily use. Double wall and vacuum insulation enhance the performance of the bottle, keeping the hot water from getting cold quickly. The bottle cap fits well with the bottle and the silicone gasket inside the cap ensures airtight seal- no leakage. Portable shape and lightweight size, you can carry this water bottle while hiking, biking, shopping or leave it at the office. Material: inner 304, outer 201 stainless steel.Heat preservation performance: 12-24 hours.Style: Sports.Style: handle.Color: white, black, yellow, blue, pink.