LOCK&LOCK double-wall water bottle, 600ml capacity, keeps warm for 8 hours, cold for 16 hours. - Brand: LOCK&LOCK - Model Name: Black Wave Bottle Tumbler - Capacity: 600ml - Functions: Keeps warm for 8 hours, cold for 16 hours - Material: 18/8 Stainless Steel - Features: Hook-type cap, double-wall - BPA Free: Yes Thank you for looking. I purchased this overseas, but it has been stored at home unused. The cap is designed to stay attached to the body, and the design is suitable for outdoor use. The bottom printing is also stylish and fashionable!