Stash in a vest, belt or in the palm of your hand for easy hydration. Big Bite™ Valve for easy sipping. Leak-proof shut-off valve. Large mouth opening for easy fill with water & ice & easy to clean. Volume indicators. Easy dry hanger loop. Empty flask collapses and folds ultra-compact to fit in most pockets. BPA/BPS/BPF free. Top rack dishwasher safe.