The Mountain Hardware Fluid 18 Backpack is hydration-ready and perfectly sized to cover an adventurous day of fast action in the backcountry, this is a surprisinglytechnical daypack. The on-the-fly compression straps allow the user to adjust load stability while wearing the pack and without restricting motion. The backpanel is held flat and stable fit with the HardWave frame sheet and air is kept moving thanks to the Breathable spacer mesh panel. The easy access, zipper-free hydration sleeve speeds refilling and fits most bladders up to 100 oz / 3 liters. The Fluid 18 has plenty of smaller storage including stretch woven side pockets for quick access, and a front panel organizer for keys, wallets and cell phones.