Osprey Aether 55 Backpack Review

As a backpacker who upgraded from a bulky 65L pack, I was looking for something lighter and more comfortable for shorter trips. The Osprey Aether 55 seemed like a good option. It boasts a 55L capacity, which is perfect to help me downsize and avoid overpacking. This review will explore the pack’s comfort features, durability, and all the compartments it offers to keep you organized on the trail. I’ll also share my personal experience after using it for a while, including the good and not-so-good. By the end, you’ll know if the Osprey Aether 55 is the right backpack for your next adventure.


Osprey Aether 55 Backpack
Capacity: 55 liters
Weight: S/M size – 2.19 kg, L/XL size – 2.21 kg (approximate weights)
Material: Durable fabric with PFC-free DWR, bluesign®-approved materials
Backpack Frame: Injection-molded AirScape™ back panel with mesh for ventilation
Additional Features: Sleeping bag compartment, hydration reservoir sleeve (reservoir not included), attachment points for optional Osprey Daylite® daypack, ice axe loops

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Comfort and Fit

The Osprey Aether 55 is designed to carry heavy loads comfortably for long days on the trail. One of the key features that makes this possible is the fully adjustable fit. The backpack comes in two torso lengths to accommodate different heights. On top of that, the shoulder straps and hip belt can be adjusted on the fly to perfectly match your body shape. This customized fit ensures the weight of the pack is evenly distributed. It reduces pressure points and keeps you comfortable throughout your hike.

Another key element to the comfort of the Aether 55 is the Osprey AirScape back panel. This panel is made with a breathable mesh that allows air to circulate between your back and the pack. This ventilation helps keep you cool and dry, especially important when carrying a heavy load on a hot day. The mesh is also padded for additional comfort. You won’t feel the frame of the pack digging into your back.

Durability and Weather Resistance

The Osprey Aether 55 is built to take on the challenges of the trail. The main fabric of the pack is tough and can handle bumps and scrapes you might encounter on your hike. It’s also treated with a special water-repellent coating that makes it rain and snow-resistant. This coating is PFC-free, so it’s better for the environment.

Even with the water-repellent coating, a heavy downpour can soak through. That’s why the Aether 55 comes with a rain cover. This rain cover is also made with a PFC-free water repellent and slides easily over your pack to keep your gear dry in wet weather. Both the pack and the rain cover are made with bluesign®-approved materials, meaning they meet strict environmental standards.

Organization and Accessibility

Staying organized on the trail is easy with the Osprey Aether 55. The large front panel zipper opens wide to give you easy access to the main compartment. This is perfect for grabbing bigger items you need throughout the day. There’s also a floating top lid with pockets for smaller things you want to keep close at hand.

For quick access to essentials, the Aether 55 has several other pockets. There’s a shove-it pocket on the front that’s ideal for rain gear or a jacket. Two stretchy mesh pockets on the sides hold your water bottles securely. The hip belt even has built-in pockets for your phone, GPS, or other small essentials you need on the go.

Additional Features

The Osprey Aether 55 isn’t just comfortable and organized, it’s also packed with features that make your backpacking trip smoother. If you’re carrying a sleeping bag, there’s a special compartment at the bottom of the pack to keep it separate from your other gear. This compartment has a divider you can remove and straps to hold your sleeping bag in place.

Another cool feature is the built-in sleeve for a hydration reservoir (not included). This lets you stay hydrated easily by simply routing the hose over your shoulder strap. Feeling adventurous? The pack also has loops for attaching ice axes and trekking poles. You can even attach an optional Osprey Daylite® daypack for short side trips without needing to carry your whole backpack.

Personal Experience

I’ve been using the Osprey Aether 55 for a few years now and it’s become my go-to backpack for multi-day adventures. It took some time to adjust all the straps for the perfect fit, but now it feels great on my back, even with a heavy load. The all-mesh back panel keeps me cool and dry, which is a major plus on hot hikes.

There’s plenty of space for all my backpacking essentials, and the pockets help me stay organized. The hipbelt pockets are especially handy for storing snacks and my phone, keeping them within easy reach. Overall, the Osprey Aether 55 is a comfortable, well-built backpack that makes backpacking enjoyable.

What I like about this pack

  • Comfort and Fit: Adjustable torso length, custom-fit shoulder straps, and hip belt distribute weight evenly for a comfortable carry. The Breathable AirScape™ back panel keeps you cool and dry.
  • Durability and Weather Resistance: Tough fabric with PFC-free water-repellent coating. Included rain cover with PFC-free DWR for additional protection. Bluesign®-approved materials for eco-conscious manufacturing.
  • Organization and Accessibility: Large main compartment with easy access. Floating top lid with pockets for frequently used items. Shove-it pocket for quick access gear. Stretch mesh side pockets for water bottles. Hipbelt pockets for essentials.
  • Additional Features: Sleeping bag compartment with divider and removable straps. Hydration reservoir sleeve. Attachment points for the optional Osprey Daylite® daypack. Ice axe loops with bungee tie-offs. Spacious design for multi-day trips.
  • Personal Experience: Comfortable for long hikes, well-organized compartments, easy access to essentials.

What I don’t like about this pack

  • Minor drawbacks: Adjusting straps can take time to get the perfect fit. Extra strap length on some adjustments might be excessive. The hip belt buckle feels a little cheap compared to other parts of the pack. Not the lightest backpack on the market (but the added weight comes with features).
  • Potential for some: Water bottle pockets might not be snug enough for all bottle sizes. The brain compartment is not removable (might be a minus for some).


The Osprey Aether 55 is a comfortable, durable, and feature-rich backpack that’s a great choice for backpackers looking for a reliable pack for multi-day adventures. While there are some minor drawbacks, the overall comfort, organization, and functionality make it a strong contender for your next backpacking trip.