Osprey Seral 4 Lumbar Pack 2026 - O/S in Black | Polyester

evo.com | Osprey Fanny Packs > With 4 liters of carrying capacity, the Osprey Seral 4 Lumbar Pack is the optimal size for the vast majority of mountain bike rides. Equipped with a 1.5L hydration reservoir, a big zippered main compartment with internal organization for bike tools, and Osprey's beloved AirScape lumbar backpanel for ergonomic comfort and ventilation, the Seral 4 Lumbar Pack is just what you need to focus more on the trail and less on combating sweaty back syndrome. Large Zippered Main Compartment with Reservoir Sleeve Main bluesign(R) approved 600D recycled PET polyester, PFC-free DWR Blinker Light Attachment with Reflective Graphic 7.5" H x 12.5" W x 4.5" D Main Compartment Tool Organization | Osprey Seral 4 Lumbar Pack 2026 - O/S in Black | Polyester