Big weight savings upgrade for a beloved backpacking pack.

Brand new and exciting for 2023, the M’s Osprey Exos Pro 55 & W’s Osprey Eja Pro 55 ultralight backpacks are slimmed down versions of their forebears, the original M’s Exos 58 and W’s Eja 58. The Pro models are offered in addition to the originals, and combine ultralight materials and a slightly smaller chassis to achieve nearly a full pound of weight savings – 33 oz vs 47 oz. (shop now)

At just under three pounds, the original Exos and Eja were a bit too heavy to be considered ultralight backpacks, but at just over two pounds, the Osprey Exos Pro 55 & Eja Pro 55 hit the ultralight backpack bullseye. On paper, the pro models are strictly superior to the originals.

• Weight:  33.2 oz
• Price: $290
• Materials: 100D recycled nylon ripstop with DWR
• Frame: 3.5mm alloy peripheral frame with adjustable suspension and tensioned mesh back panel
• Load Capacity: 30 lbs
• Internal Volume: 46
  
• External Volume: 9L lid + pockets
• Pros: Comfy. Excellent weight transfer. Ultralight. Recycled materials. Good back aeration. Osprey guarantee. Very easy adjustable fit.
  
• Cons: Bulky. Frame might be delicate, is tall and prevents head from looking upwards or wearing 360 brim. Use of delicate stretch mesh. Side pockets are too tall/narrow. Straps everywhere.

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Features

As ultralight backpacks go, the Osprey Exos Pro 55 & Eja Pro 55 are about as fully-featured as one can hope for. The aeriated foam shoulder and hip belt connect to an adjustable external frame system that transfers weight very comfortably and lifts the back panel off the back with a taught mesh surface for maximum ventilation. See above.

This is referred to as a trampoline style. The taught mesh prevents lumps from jabbing you, and allows air in between pack and back. However, the downside is that it carries weight farther behind the wearer, which subtly and ever-so-slightly pulls you backwards and changes your balance. You probably won’t notice it, but it’s a minor drawback to go along with the comfort boosts.

It also features a full sized, detachable lid with 9L of storage perfect for storing all of your day-use knick-knacks. It has two hip belt pockets, and three mesh pockets spanning the sides and back, as well as an internal water bladder sleeve. The top of the inside compartment has its own dedicated lid/cover, a cinch, and a compression strap. Both combined are a bit overkill in our opinion (See above). For funsies, it has a reminder of LNT printed on the inside of the inner lid.

We love the adjustable sizing feature of the frame. It is extremely easy to adjust the toggles between the four heights, which allows for about four inches of adjustability. It is one of the best frame adjustment systems we’ve used (see below).

Difference between pro and original models

Aside from the most important difference of all, a pound of weight savings – there are few major changes in features between original and pro. But we’ll call out what can. First, the rear external pocket is now mostly nylon ripstop, with mesh used only for stretch paneling on the sides of the rear pocket. This is definitely an upgrade as the mesh used on the original packs would constantly get microtears and now there is less susceptible surface area. That type of typical wear and tear won’t effect the pro model as much. However, the narrow stretch mesh panels on the sides of the rear pocket will now bear more of the load, be stretched more taught, and will be more prone to snagging/getting caught on a branch in bushwhacking scenarios.

The hardware like clasps and buckles got smaller than the original, and might be a bit fiddly and more prone to breaking. We don’t think dinky buckles are the best way to save weight, but these aren’t tiny. Just a bit small.

One interesting change from the original is the use of a non-secure, elastic closure left hip belt pocket (see below). This allows for extreme easy access to items, perfect for constantly pulling your phone out to take picks, or leaving an bag of snacks open. We will continue to like this until we loose something out of it, and then maybe we’ll change our minds. Time will tell. The right hip belt pocket is zippered as usual.

But as the overall design is basically the same, the Pro models derive most of their weight savings from material upgrades. Comparing listing, that translates to slimmer frame architecture by way of 3.5 alloy rods, instead of 4mm.

We presume this is why the load capacity is rated to 30 down from 35. The Pro’s also use “NanoFly™: 100D Nylon x 200D UHMWPE ripstop” compared to the originals which are sewn with “bluesign® approved recycled 100D high tenacity nylon ripstop.”

As Osprey has not provided additional fabric performance info, we’re left to assume that the new material is lighter and has a superior durability-to-weight, but that the older material is heavier but still has a better total durability, and is also more eco-friendly. Lastly, we’ll note that Pro models cost only $30 more than the originals, which is an incredibly good deal for nearly a pound of weight savings.

What could be better

It’s rare for us to say that any pockets are too deep, but we do feel that way with the Osprey Exos Pro 55 and Osprey Eja Pro 55 backpacks. They are taller than an entire 1L Smartwater bottle, which makes them a bit fussy to use, especially considering that static compression straps criss-cross them and can interfere with sliding objects in and out. Conversely, they are high volume, and can easily hold 2L of water each.

We also wish the side pockets were made with burlier, static materials that protruded from the sides, rather than wrapping around flush with stretch mesh. It’s just easier to use and less prone to tearing. While they do have the side-access, we’ve never had much luck with that, but maybe it just takes better shoulder mobility.

Also notable, this pack suffers from straps galore. The compression optionality is nice to have, but seriously, there’s just too many straps. Collectively, they’re more likely to get in the way and interfere with your use of external storage than they are to be helpful in compressing.

The zippered hip belt pocket on the right side could also use more girth. It’s a large but-thin-pocket and we wish it had a boxier, roomier construction. See below.

Another area for improvement is the height of the frame. It’s tall enough that it prevents you from craning your neck backwards to look up at the sky. And the more taught the load lifters, the less backwards mobility your head will have. And don’t even think about wearing a 360 brim sun hat. Because the frame is so tall, if you’re in between sizes, we recommend sizing down as adjusting the torso on the L/XL to the smallest setting will make the pack a few inches taller still, further accentuating the height issue. This author’s back is dead center on their size chart between S/M and L/XL, and it’s hard to comprehend why they didn’t make a M/L, as that would have likely been the most popular size.

Verdict

This is likely one of the best Osprey brand backpacking packs that they’ve ever produced, and at just over two pounds, it is also the lightest, and it’s actually ultralight. It is comfy, does an excellent job of transferring weight, and has lots of external storage. Our biggest complaint is the bulkiness, and height of the frame, and the use of stretch mesh instead of more durable materials on the external storage. And this is def not durable enough for Thru-hiking. But it’s still a pretty good overall backpacking backpack, all things considered.

Compare this to more great options in our guide to the best ultralight backpacking backpacks of the year.