Convert your Nathan soft flask into an easy-to-drink front vest hydration piece. If you prefer to keep your hydration on the front of your running pack instead of the back, simply add the Nathan Extended Straw with Bite Top 2-Pack onto your Nathan soft flask for hands-free hydration on the go. Details: Two pack Fits on all Nathan soft flasks Bite valve keeps liquids from escaping Convert any soft flask with these straw tops