This is a hydration tube from Osprey Hydraulics. The entire tube is covered, providing insulation and preventing freezing. I purchased it three years ago and have stored it at home. Although it is unused, please understand that there may be some slight discoloration. *I am also listing this item on other platforms, so if it sells simultaneously, I may have to cancel the transaction. Thank you for your understanding. Also, please refrain from excessive inquiries or investigations. I had a difficult experience with a buyer in the past who made what seemed like threatening demands. They refused to cancel the transaction and ultimately left a negative rating of 1, even though they were not satisfied. I hope for a pleasant transaction.*