The Guide's Edition Synapse 25 in Deep Blue (dark blue) 525 Ballistic. The Guide's Edition Synapse 25 in Mars Red 525 Ballistic. The Guide's Edition Synapse 25 in Black 525 Ballistic. The Guide's Edition Synapse 25 in Aubergine (dark purple) 525 Ballistic. The Guide's Edition Synapse 25 in Constellation (light blue) 525 Ballistic. The Guide's Edition Synapse 25 in Nebulous Grey (Medium grey) 525 Ballistic. The Guide's Edition Synapse 25 in Coyote (brown) 525 Ballistic. The Guide's Edition Synapse 25 in Ursa (brown-grey) 525 Ballistic. The Guide's Edition Synapse 25 in Wilderness (forest green) 525 Ballistic.
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Color: Mars Red Ballistic/Coyote 210 Ballistic

A limited edition version of our Synapse 25 backpack designed for the trail. Includes a removable internal frame.

25 liters / 1526 cu. in.

We've retired the Guide's Edition Synapse 25 so we can focus our efforts on other projects. You can sign up for our newsletter at the bottom of the page to receive updates on what we're working on next!


The Guide's Edition Synapse 25 takes all of the same clever features, bountiful organization, and top-shelf build of the original Synapse 25 and walks it all a bit further up into the mountains, a bit deeper into the woods.

Rather than the all-too-common black zippers, hardware and webbing, the Guide's Edition Synapse 25 has gone terrestrial: it’s trimmed and lined in Coyote brown. The resulting aesthetic might be taken as an homage to another time; but to our sensibilities, bags trimmed in Coyote seem to be a little more at home in the great outdoors. Brown blends in more readily with natural surroundings and doesn't show dirt as much. When it does get a bit dusty or dirty, it looks like it's supposed to. You might also find that the Guide's Edition S25’s rugged good looks solicit more than a few smiles of appreciation when you’re back wandering the canyons of Gotham.

And it's not just about the practical and handsome coyote trim–we've added several features to the Guide's Edition Synapse 25 that allow you to carry gear specific to slightly more adventurous outdoor adventures: 

New Edgeless EV50 1/2" Shoulder Strap

Conformity is overrated — except, perhaps, when it comes to shoulder straps. The edgelessness of our Edgeless EV50 1/2" Shoulder Strap allows it to more softly conform to your shoulder; we find that this increases comfort. Yet the straps aren’t too soft: the 1/2” thick foam means the strap is robust enough to carry a heavy load.

Included Removable/Adjustable Internal Frame with Pre-Curved Aluminum Stay

The Guide’s Edition Synapse 25 includes an internal frame of die-cut .055” thick High Density Polyethylene (HDPE), with a nylon webbing sleeve sewn down the center that encases a removable 1” /25mm wide 6061 aluminum stay. We’ve bent the stay to a generic spinal curve but we recommend you re-bend and/or adjust the curvature to best fit your own back (video instruction here). Along with the included webbing hip belt or optional Padded Hip Belt, the Guide’s Edition Synapse 25’s internal frame enables you to shift some of the weight of the fully loaded bag on to your hips. Another reason to use an internal frame? It ups the ante on comfort if you over-pack or don't pack carefully: the frame keeps an overstuffed pack from barreling out against your back, and also prevents pointy objects inside from poking you. For more on internal frames—how they differ from "frame sheets" and the pros and cons of using one—see our Guide To Backpack Frames.

The internal frame secures via the same rail loops as our optional Cache laptop/tablet sleeve (don't worry, you can secure both the frame and a Cache to the same set of rail loops!) and a clever “T” bar holds the frame in place relative to the loops.  The lower edge of the internal frame floats freely—in all of our testing, we’ve found this isn’t much of an issue as the bag’s contents tend to keep this lower extreme in place. Your Guide's Edition Synapse 25 will come with its internal frame installed; here's instructions (text and video) on how to install and remove the internal frame.

Are you getting excited reading all of this and wishing your current Synapse 19 or Synapse 25 could have an internal frame? You can! This very same internal frame (with black trim) is also available for the regular 19 or 25: see the Synapse 19 or Synapse 25 Internal Frame page to purchase internal frames for those two bags separately.

New! Ice Axe Loop and Accessory Strap Holders

The center front of the Guide's Edition Synapse 25 has one diamond accessory strap holder and a corresponding ice-axe loop below, allowing you to carry an ice axe for high-country, early-season mountaineering. If you go that route, or think you're gonna secure something else similar to the front (say, a camera tripod) make sure to pick up an optional Ice Axe Lash Strap. Being the thoughtful types we are, we added an additional zipper slider -- that makes two, not just one -- on the bottom pocket of the Guide's Edition Synapse 25. In the event that you decide to strap an ice axe or tripod on the front of the bag, the two zipper sliders will make it a little easier to access the contents of that front bottom pocket.

In addition to the diamond strap holder, we've added two strap holders on the bottom. If you opt for the optional Lash Straps (sold in pairs), you can secure foldable hiking poles, an ultralight folding chair, icy gaiters or a wet raincoat to the bottom of the pack.

As with the regular Synapses, the Guide’s Edition has a 1.5" / 38 mm webbing loop on the exterior bottom pocket that's ready to accept a Guardian Light—highly recommended if you ride a bicycle or walk in the dark.


Like the regular Synapse 25, the Guide's Edition is carefully calculated and supremely organized. 

Conformity is overrated — except, perhaps, when it comes to shoulder straps. The edgelessness of our Edgeless EV50 1/2" Shoulder Strap allows it to more softly conform to your shoulder; we find that this increases comfort. Yet the straps aren’t too soft: the 1/2” thick foam means the strap is robust enough to carry a heavy load.

We tend to recommend that folks under 5'6" / 1.70 m (or those who just want a smaller bag) check out the Guide's Edition Synik 22. However, this is not to say that the Sypanse 25 won’t fit you—a number of us who are between 5’1” / 1.55 m and 5’5” / 1.68 m use it all the time and find it fits very well. Regardless of your height and build and no matter which bag you get, it’s a good idea to test it, fully loaded, for fit and comfort.


The front of the Synapse 25 has five zippered pockets, all of which zip shut with #8 YKK Aquaguard® water-repellent zippers.

The top center front pocket is deep enough for a 1-liter water bottle or hydration bladder (a 2-liter hydration bladder will also fit as long as it's not overfilled). This pocket centers your water bottle perfectly so it won’t throw the bag’s weight to the side. We’ve put one O-ring in this pocket, because why not?

Below the bottle pocket is another small zippered pocket, also with one O-ring: it's just deep enough for keys, a wallet, or glove liners.

The side pockets are generously sized for sunglasses (in a case or alone), a first aid kit, or even a light jacket or down vest compressed in a stuff sack (like our Travel Stuff Sack). The right side pocket has a small organizational pocket; the left pocket has one pen/pencil slot and two wider slots for multitools, knives or just more pens. Both side zippered pockets have one O-ring—you’ll find an 8" / 200 mm Key Strap attached to one of them. Tucked inside of one of the side pockets is a pack of 8 inch Cord (8 Pack) in Coyote so you can tie your own zipper pulls; additional cord in other colors is available on the Cord Zipper Pulls page. 

The bottom front pocket of the Synapse 25 is a great spot for extra clothing or snacks and will easily accommodate a thin wool/fleece sweater, light down jacket, or rain jacket. If you care to add organization, it's more than big enough for a 3D Organizer Cube (MeshHalcyonParapack, or Clear), Side Effect, or Cubelet. You can tether your cubes with a Key Strap to one of the three O-rings inside this pocket.

The Synapse 25’s main compartment can hold large, flat items like notebooks or laptops—it closes with a #10 YKK Aquaguard® water-repellent zipper. It has two O-rings for you to attach Organizer Pouches or other items. Also inside the main compartment are the aforementioned rail loops to which you can attach the internal frame or the optional Cache, which is available in sizes specifically for every Apple laptop and iPad (PC users, click here to take a look at our Laptop Fit Guide). Adding the Cache makes the Synapse 25 a "checkpoint-friendly" laptop backpack—see here for how it works. One pair of loops is on the rear side of the compartment, and the other is on the front. This means you can have your laptop or tablet against your back or against the front of the bag, whichever seems more comfortable or convenient.

Also inside the main compartment is an elastic-topped, open-top pocket, sized generously to fit a few books or an extra pair of shoes. It can also hold a Tri-Star Medium Packing Cube, perfect for storing a change of clothing. The open-top pocket will also fit some sizes of Cache, including the 11" Air, iPad, and iPad mini sizes. (If you plan to carry a water bottle in the water bottle pocket and also an iPad or other device in the open-top main compartment pocket, make sure the device is protected with a Cache or a similar protective sleeve: the water bottle pocket is directly in front of the open-top pocket and your device is best protected from your hard water bottle.) 

The remainder of the main compartment opens wide, ready to accept whatever larger items you're packing.


The exterior of the Guide's Edition Synapse 25 is made of 510d 2x2 HT Ballistic nylon that’s as tough as 1000d Cordura® but smooth, so it collects little snow, pet fur or sweater lint. For the interior lining, we chose 210d 2x2 HT Ballistic nylon in Coyote Brown—because it's lightweight, tough, and beautiful.

The back panel is padded with 1/4", closed-cell foam with an exterior of Dri-Lex® Aero-Spacer® mesh and 210d 2x2 HT Ballistic nylon. This combination of mesh and smooth nylon is designed to provide maximum breathability (we even tested it: see here) while still being gentle on your clothing. The shoulder straps are padded with .375" / 10 mm EV50 closed-cell foam and feature an underside of ETC knit to keep you cool and comfortable. The Guide's Edition Synapse 25 features adjustable and removable sternum and waist straps with leave-no-trace hardware, a design inspired by nature: if you don't like or don't use your waist or sternum strap, remove them and leave (almost) nothing behind. Finally, at the top of the Synapse is a webbing loop: use it to hang the bag on a hook on the cabin door, or—even better—to help hoist it up and onto your back as you leave for your next adventure.


525 denier Ballistic exterior fabric
210 denier Ballistic fabric lining
Dri-Lex® Aero-Spacer® mesh upper back
210 denier Ballistic lower back
Closed-cell foam back
Edgeless EV50 1/2” / 12mm shoulder straps (EVAZOTE® OEKO-TEX® foam)
Tough Duraflex®, Nexus, and Woojin buckles and related components
#10 and #8 YKK Aquaguard® water-repellent zippers


Dimensions: 13.4" (w) x 20" (h) x 9" (d) / 340 (w) x 508 (h) x 230 (d) mm
With the included removable internal frame: 2 lb 10.7 oz / 1210 grams
Without the included removable internal frame: 2 lb 1.1 oz / 938 grams
Volume: 1526 cubic inches / 25 liters (ASTM Standard Measure)
Removable 1" / 25 mm webbing waist strap included; padded 1" waist strap optional
.375" / 10 mm padded and contoured backpack straps with .75" / 20 mm removable sternum strap
Total O-rings: 9 (2 in the main compartment; 1 in the top center pocket, 1 in the small center pocket, 3 in the bottom front pocket; 1 in the left side pocket; 1 in the right side pocket)
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Rated 5.0 out of 5 stars
Based on 2 reviews
100%would recommend this product
2 reviews
  • Sandrine
    Verified Reviewer
    Bought For Myself
    3 months ago
    Bought For Myself
    Rated 5 out of 5 stars

    Dommage d’arrêter des sacs tels que ceux là.

  • Rei
    3 years ago
    Rated 5 out of 5 stars
    I was drooling for a year before being able to buy it, I drool over each times I take it

    I got mine in 2018 (fall)

    I was drooling over for a year before being able to buy it, I drool over each times I take it

    I fell in love with the old fashioned hiking look & earthy colors (so dreamy) ;

    I fell in love with added modularity: Ice Axe Loop and Accessory Strap Holders system increases its potential so much :

    - I could carry a lacy sunshade thanks to the Ice Axe Loop + centered Diamond Strap Holder ;

    - I can tie a light camping tent thanks to the bottom straps sytem ;

    *** I was already interest in the standard version of the bag (I made a review on Synapse 25 page) ***

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