The Caldera pack is available in two sizes, granting every backpacker access to this versatile pack. The main compartment has a horizontal divider to keep your gear organized and easily accessible. The lower portion of the pack can be accessed quickly from the large #10 zipper. The main portion of the pack can be loaded from the top with an extendable and removable top lid, that doubles as a fanny pack. Behind the front wing lashing system sits a generous front access zipper allowing you to find exactly what you need without unpacking everything. The side pockets offer room for trekking poles and water bottles to keep you hydrated. 2538872 Black/Gray 7739911 Reservoir 3.0