Hydrapak Big Sur Fabric- 420 Double Ripstop 300 Double Baby Rip Weight-1lb 8 oz .68 kg Backpacks Volume-400 cu. in 6.6 Liters Hydration Bladder Reservoir Size 100 oz. / 3L Additional Features -Integrated Slider Chest Strap,Quantum Clip,Plug-n-Play Reservoir Tube Connector,Padded and Stowable Hip Belt,Top or Bottom Tube Routing option