Carrying on the Osprey legacy, the customizable Argon 85 pack for extended trips offers impressive load transfer, saving your back and shoulders. AirScape backpanel features three sections of ridged foam and a central air chimney for increased ventilation. BioForm CM A/X hipbelt has heat-moldable laminated foam and internal seams providing a personalized fit while relieving hipbone pressure. Ospreys certified Custom Molding available in most stores-check your local REI store for a custom hipbelt molding oven. Lightweight, removable sil nylon AquaSource hydration sleeve converts to a hydration pack for day-tripping reservoir sold separately. Removable top lid has one compartment with a waterproof zipper and lash-on points converts to a lumbar pack with AirScape lumbar pad. ReCurve supsension optimizes fit and load transfer features an HDPE framesheet, two aluminum stays and dual aluminum rods. Running down the sidewall, ReCurve aluminum rods create a pretensioned lift mechanism that resists sag and actively transfers load to hips. Load-lifter straps act with ReCurve rods and framesheet to draw load snug against your back for increased control and stability. Gender specific, the interchangeable, laminated dual-density shoulder straps adjust easily to fit a mans shoulder and chest contours. Provides complete access to main compartment via top-loading and side zippered openings. Externally accessible, wide-mouth sleeping bag compartment accommodates large synthetic bags. Side pockets, one zippered and one mesh, keep essentials handy and secure and double as slots for hauling skis A-frame style. StraightJacket wings let you securely compress the contents of the pack, whether its full or nearly empty, without sag or load distortion. Wings buckle across the front when full for small loads, connect straps to buckles at the edge of the backpanel, cinching one panel over the other.