The Klean Kanteen Wide Mouth 64 oz. stainless bottle has an extra wide opening, which is more than 2 inches in diameter for quick filling, pouring and cleaning. It is made from high quality, 18/8, food-grade stainless steel that's totally free of BPA and other toxins. A Loop-top screw cap uses BPA-free polypropylene on the outside and food-grade stainless steel on the inside so your water does not come into contact with plastic. The loop top lets you attach the bottle to a backpack or belt loop using a small, lightweight cordage or a biner of your choice (a biner does not come with the bottle). This bottle measures 10.4" tall by 4.3" wide. Warning: Never freeze your Kanteen as it can cause serious damage and void the lifetime warranty. The Kanteen is not designed for hot liquids as it it single walled.