For committing thru-hikes where every gram counts, the 55-liter Eja Pro provides the most comfortable carry in its weight class. Shedding nearly a full pound off from the Eja 58, the Pro features a more fine-tuned adjustment system for its ventilated AirSpeed™ suspension system with anatomical women's fit. Comfort, without weighing you down. KEY ATTRIBUTES AIRSPEED™ SUSPENSION A tensioned mesh backpanel keeps the weight off your back, enabling highly ventilated carrying comfort. Osprey Eja Pro 55 Litre Womens Ultralight Backpack