continuing the deluxe custom fit legacy with Recurve suspension and BioForm A/X components, the Osprey Argon for men is the most customizable and comfort oriented packs. Features include a 40d Sil Nylon AquaSource that converts to a hydration pack with padstraps, vertical zip access into main body, wide mouth sleeping bag compartment, top lid that converts to a lumbar pack with AirScape lumbar, and zippered easy access side pocket