Double-wall stainless steel vacuum construction with copper insulation, which allows beverages to stay cold for 24 hours or hot for at least 8 hours. The construction also prevents condensation on the outside of the bottle. Screw-on lid with twist-open leak proof cap allowing for 360 drinking. Wide mouth opening for easy cleaning and filling. On-trend, durable powder coating. Volume capacity is 350ml. Lifetime guarantee for manufacturing defects with Got Your Bak.