Ultra durable, BPA free with FDA approved polyethylene inner liner. When chill overnight and you will have a refreshing beverage anytime throughout the day. If full this water bottle stands upright, the space saving, rollable and foldable with metal carabiner for clip-on and storage, or flattens when not in use for easy storage. Great for running, cycling, backpacking, hiking, camping, traveling, or even everyday errands.