An update to Nathan's popular soft flask handheld that started it all, this 14-ounce version features an integrated hand strap and rigid ExoSpine™ for superior comfort and efficiency. 14 oz /414 mL BPA-FREE soft flask with bite valve The rigid ExoSpine™ creates superior hand feel and support for the soft flask Ergo-designed hand-strap provides grip-free comfort, and maximizes running efficiency Soft flask can be easily removed from sleeve, and used in NATHAN hydration vest pockets Breathable wicking mesh under hand position provides superior grip Small stash pockets for gels or a key Specs Storage Capacity: 8.5 cu in/0.14 Liters Weight With Soft Flasks: 2 oz/59 g