Maxpedition Fatboy Versipack

Perfect for the day hike, holds a lot and is well balanced.

Has many attachment points for more gear/water/gps you name it.

(from http://www.maxpedition.com )

The Maxpedition Fatboy Versipack (#0403) is more than a durable, ergonomic shoulder sling pack; it is the state-of-the-art portable gear organizer that provides secured containment for and rapid accessibility of daily equipment. The versatile main compartment has a huge 156 cu. in. of space with a water-resistant storm collar that can be deployed by pulling a cord-locked drawstring. An array of integral fixed-position external pouches retains and indexes individual pieces of gear while two sets of nylon webbing anchors accommodate MAXPEDITION's modular expansion accessories such as the CP-L Radio Holster. It also has a 2" wide Velcro loop patch on the front lid for attachment of ID patches. Each Fatboy comes with a tactile non-slip shoulder pad providing great comfort during extended use