The Klean Kanteen Wide water bottle is a full stainless steel water bottle designed to last a lifetime. Created as a safe, BPA-free, nontoxic alternative to plastic water bottles over 10 years ago. Crafted from high quality, durable food grade 18/8 stainless steel with a wide 2.125 inch (54mm) opening which is easy to fill, pour and drink from. Single wall stainless steel construction is lightweight, perfect for hydration and keeping drinks cold in the cooler or in the fridge. Included Wide Loop Cap has a stainless steel bottom to create an all-stainless interior. Electropolished interior and rounded corners make the Wide 64oz water bottle easy to clean and maintain. Wide-mouth opening is compatible with most backcountry water filters and UV sterilization devices, making the Wide 64oz a favorite among backpackers. All Klean Kanteen products are made using safe healthy materials and backed by the Strong as Steel Guarantee.