feature: Made of double-layer 304 stainless steel, food-grade plastic cover. Keep warm/cold for 8-10 hours. Leakproof, BPA free. Specifications: Capacity: 380ml, 510ml. Size: 380ml: 14.5 * 7cm, 510ml: 17 * 7cm Color: black, white, blue, red, green. The package includes: 1 x coffee mug. For the first use, please pour 100 degrees of boiling water and leave it for 1 hour, then pour it out and you can use it.