Osprey Seral 4 Lumbar Pack - One Size Postal Blue Model=AirZound Horn hex key inner axle for

hex key inner axle for easy maintenance

Machined aluminum axle spacer for fine tuning hub spacing or as replacement axle spacer

1/2-13 x 9

and labyrinth end cap design

Control Flex Shank: Medium-soft Flex control for great comfort

Osprey Seral 4 Lumbar Pack - One Size Postal Blue Model=AirZound Horn hex key inner axle forOsprey Seral 4 Lumbar Pack One Size Postal Blue. The Osprey Seral lumbar pack is perfect for the minimalist looking for something other than a traditional over the shoulder pack. The Seral features a dedicated hydration compartment that stores an included 1. 5L lumbar reservoir and compresses for stable carry. Dedicated hose magnet attaches the bite valve for easy access. Easily accessible zippered main compartment with internal tool organization Dual