The Exped Traverse 40 Backpack is a lightweight alpine style backpack with an innovative frame that can be curved when you want more airflow for back ventilation or flattened when you need a backpack that hugs your back and hips more closely. A convenient rear hatch also provides panel-style access to gear buried deep in the backpack, making this a good pack for travel as well as longer day hikes.
Specs at a Glance
- Volume: 39 liters
- Torso Length Range: 17.7 – 21.7 in
- Weight: 43 oz (47 ounces, actual tested)
- Frame: HDPE framesheet with spring steel reinforcement
- Fabric: 210 D Robic HD Ripstop nylon, PU coated, 1500 mm water column
- Rain cover included
Internal Storage and Organization
The Traverse 40 is a top-loading backpack with the non-floating top lid pocket. The lid has two pockets: one on the underside of the lid and a larger one on top for maps, gloves, hats, and personal items.
The main compartment is accessed from the top or from the rear through a panel-style hatch. It has an internal hydration pocket and a single hang loop for suspending a water reservoir. There are also mesh pockets on the interior sidewalls of the pack (at the base) that are good for organizing socks or other small clothing items. The rear hatch door has a mesh pocket on the inside and a solid pocket on the hatch exterior, which are good for storing maps and smaller items. Both close with zippers. Unfortunately, there’s no place to store wet items, like clothing or a dripping wet water filter in a pocket where it won’t soak through the pack and make your gear wet.
There are two water pleated water bottles on the sides of the backpack, which are easily reachable while wearing the backpack. Both are faced with solid fabric for better durability. The pleats make it possible to expand the size of the pockets so they can hold two bottles, without requiring an elastic hem or mesh. An external compression strap is used to shrink the pocket-size when additional capacity is not needed. The pleats are also necessitated by the curved frame, which I’ll discuss further below.
The Traverse 40 also has a bottom rain cover (included) pocket in the base of the pack. The rear panel pocket makes the use of a rain cover mandatory if you want to be able to use the rear pocket to access gear, since lining the pack with a waterproof plastic bag will block hatch access.
Finally, the hip belt has two very large zippered pockets, both solid faced, that are ideal for storing snacks or electronics. I wish all manufacturers made their hip belt pockets this large.
External Attachment and Compression System
The Traverse 40 has two tiers of side compression straps if you include the strap that is used to adjust the volume of the side water pockets. The straps are made with webbing, not the cheap elastic cord that some pack manufacturers use.
There are 4 webbing gear loops arranged on the corners of the packs back that you can use to secure additional gear the back of the pack, in addition to four gear loops on the top lid. These are all sewn into the seams of the pack for maximum strength. You’ll need to supply your own webbing straps or elastic cord, but they’re easily attainable.
Finally, the Traverse comes with a pair of trekking poles holders. These are attached to two of the webbing gear loops on the rear of the pack.
Frame and Suspension System
The Traverse 40 has what Exped calls a Switchback frame, which lets you curve the frame of the backpack on demand in order to increase the amount of ventilation between the pack and your back. When it’s not needed, you can release the Switchback system, and the frame will return to its original flat state.
While ventilated backpack frames are comfortable, they can throw you off-balance because they move the concentrated mass of a backpack load farther away from your hips and abdominal muscles. This is most noticeable when you’re scrambling and the added momentum of the load can result in a fall. The Switchback frame system lets you choose when you want a curved and ventilated pack, vs a flat one, with very little added weight over a conventional frame.
The degree of curvature is adjustable by the wearer using a strap running down the center of the back panel. Pull to create a curve and release it to make the back flat again. When curved, your back rests against the center strap, which feels odd at first, but quickly becomes less noticeable. As expected, curving the back panel greatly enhances back ventilation, helping keep your shirt dry on hot and sweaty days.
What makes this frame tick? The Traverse 40 frame has two components: a flexible HDPE sheet that runs behind the mesh back panel and slots into the belt with two vertical wire stays that help stiffens it. The wire stays stop short of the hip belt, however, which limits the max amount of weight that the pack can comfortably carry to about 20 pounds.
When the Switchback system is engaged and the frame is curved, the torso length of the pack shortens along with it, moving more weight on to the shoulders and less on the hips. It’s quite noticeable and another reason for keeping the max recommended load low. If you try to curve the Traverse 40 frame when the pack is tightly packed, it’s very difficult to get it to curve because there isn’t any room left in the main compartment, which has to shrink when the frame bends inward. The geometry of the water bottle pockets also changes, getting smaller and tighter. That explains the need for the pleated water bottle pockets on the side of the pack in order to provide more pocket volume.
Rather than changing the curve frequently, you’d be better off setting up the Switchback frame with a gentle curve that improves on the ventilation provided by the flat frame orientation and leaving it alone thereafter. Otherwise, you’re going to have to constantly fuss with unpacking and repacking your pack as the interior volume changes. The other alternative is to just use the Traverse 40 with a flat frame since it’s still a perfectly good pack in that configuration.
I think that setting the expectation that you can switch back and forth between a curved frame and a flat one without any side effects is an issue with this pack, not the actual Switchback frame itself. There’s value in being able to personalize the curvature for individuals without the need for an ornate and heavy “anti-gravity” system when a simpler, minimalist solution like the Switchback works so well. It also makes it possible for Exped to sell one backpack to people who want a curved frame vs a flat one, instead of having to manufacture and sell two separate models. I guess what I’m saying is that the marketing and documentation around the Switchback frame need to be tweaked to explain how to use it best.
Exped’s Switchback frame is also available on several smaller backpacks designed for day hiking use: Skyline 15, Skyline 25, and the Traverse 35. I have the Skyline 25 and it’s become my goto daypack. The Switchback frame works better on a daypack because I never need to stuff it to the gills like I do with a higher volume backpack. Shortening of the torso is also less of an issue because on smaller volume day packs since the loads you need to carry are so much lighter weight.
The Exped Traverse 40 is a lightweight top-loading backpack with a “Switchback” frame that lets you change the curvature of the pack’s back panel to increase the amount of back ventilation you want. While it works fine when the main compartment is packed loose, it’s difficult to adjust when the pack is full of gear for an overnight backpacking trip. When curved, the Switchback frame also shortens the pack’s torso length, which can put more of the load on your shoulders instead of your hips. As long as you don’t stuff it tightly or try to carry more than 20 pounds, the Traverse 40 makes a good day pack. That said, it would be very interesting to see the minimalist Switchback frame concept applied to a higher volume frameless ultralight backpack (sub 18 ounces) to provide back ventilation.
Disclosure: Exped provided the author with a backpack for this review.