The double-layer thermos flask features a 304 stainless steel inner layer and a 201 stainless steel outer layer. This innovative design guarantees superior thermal insulation, and resistance to oxidation and corrosion, and ensures a clean, pure taste for your beverages. With a generous 550ml capacity, this insulated water bottle is your ideal companion for staying refreshed at work, the gym, on the go, or during daily activities. The convenient loop handle on the lid enhances portability for your active lifestyle. Additionally, the logo can be customized to suit your branding needs.