The updated Nalgene water bottle features the classic narrow mouth and very high quality construction, available in various colors and made in a much more environmentally friendly way. It is made of 50% recycled plastic. It is 100% leak-proof without an o-ring or other sealing components. By unscrewing the cap, it is very easy to clean and refill the bottle. The diameter of the bottle is 29mm and the capacity is 1000ml. Nalgene bottles are ideal to have in your backpack or bag at the office every day. They are also perfect for your hikes and travels, as they are very durable.