The biggest of the Fox collection of hydro packs, UTILITY 18L, comes with a 3 litre HydraPak reservoir for liquids and a total volume of 11.6 litres. The removable HydraPak reservoir offers an easy access, water line to mouth with 45° valve. The backpack features a lined Fleece electronics pocket, a quick access zipped pocket, elastic mesh side pockets, side compression straps to stabilize contents, a tool binder, reflective elements, fully adjustable shoulder straps, a back panel in structured ergonomic profile, and an integrated key ring.