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Boreas Gear Buttermilks 55 Backpack

Boreas Gear Buttermilk 55 Backpac k- Front and Side Mesh Pockets on
Boreas Gear Buttermilk 55 Backpack – Front and Side Mesh Pockets on

The Boreas Gear Buttermilks 55 is a lightweight backpack suitable for weekend or multi-day backpacking trips. Although it’s a bit on the heavy side at 3 pounds 1 ounces, the Buttermilks combines the simplicity of a minimalist ultralight-style backpack with the load carrying capabilities of a more conventional frame system. The Buttermilks will appeal to hikers who want one backpack suitable for rough and tumble backcountry adventures that can serve double duty as an elegant and functional travel backpack.

Organization and Storage

The storage layout on the Buttermilks 55 (3356 cubic inches) is simple and straightforward with a large main compartment and extension collar, an open-topped front shovel pocket and side stretch pockets made out of robust softshell-like fabric, and large hip belt pockets.

Boreas Gear Buttermilks 55 Backpack: Lidless Top
Lidless Top

The main compartment contains a hydration pocket and hang loop, including dual hydration ports. The front shovel pocket is cavernous, providing an excellent place to hold jackets and other clothing layers without needing to open the main compartment. The side stretch pockets are similarly well sized and can easily fit 1 liter water bottles, although small objects may fall out of side openings that make it easier to reach back and pull bottles out while wearing the backpack.

The main compartment of the Buttermilks 55 closes with a draw string closure, enabling the pack and extension collar to be overstuffed with extra clothing and gear. While lidless tops are commonplace in the lightweight backpacking world, it is unusual to find backpacks that do not a fabric flap or roll top closure to prevent rain from pooling on top of the extension collar and leaking into the main compartment.

While you can roll up the extension collar fabric on the Buttermilks 55 to mimic a roll type closure, doing so reduces the maximum capacity of the pack and there’s nothing to prevent it from unfurling. The only reliable way to prevent rain from entering the main compartment is to use the included rain cover (3.2 ounces), a sub-optimal solution to a well understood backpack design issue, and one that may turn away users who dislike using pack covers.

Boreas Gear Buttermilks 55 Backpack: Rear Pocket
Rear Pocket

The Buttermilks 55 also features a front facing zippered pocket situated above the top of the shovel pocket which is large enough to store a map and other smaller items you want to keep easily at hand like a headlamp, compass, gloves, hat, SPOT 3, or smart phone. Lined with a vibrant blue fabric, items in the pocket are easy to locate, making this extra pocket is a welcome convenience and unique design statement.

Backpack Frame and Suspension

The Buttermilks 55 has a surprisingly robust and rigid frame system capable of comfortably carrying loads up to 35 pounds. This is achieved using a plastic framesheet that is reinforced with an aluminum wire frame that runs 360 degrees around its perimeter. The framesheet slots into a fabric compartment inside the main compartment of the pack although it can be removed, saving 10.4 ounces of  pack weight, if carrying lighter loads. This is nice feature for travel because removing the aluminum frame can help expedite TSA screening at airports and  make the pack easier to stuff into an overhead compartment.

Boreas Gear Buttermilks 55 Backpack: Ventilated Foam Backpad
Ventilated Foam Back Pad and Integrated Hip Belt Pockets

The back of the Buttermilks is covered by a mesh-covered, ventilated back pad which helps dissipate perspiration. The padding is quite comfortable and gets softer the longer you wear the pack, conforming to your body shape for a personal fit.

Load transfer to the hips is further enhanced by the fact that the hip belt is sewn to the pack body. Load lifter straps are also included, attached to the pack at the top of the framesheet and wire perimeter frame helping to pull the load forward into better hip alignment.

Unfortunately, the Buttermilks’ hip belt sizing is quite limited and only appropriate for tall and skinny people. For example, a size medium for someone with a 18-20″ torso length is only available for people with a waist size less than 33″. If you have a larger waist than that, you should look at other backpacks.

Boreas Gear Buttermilks 55 Backpack: Side view of backpanel foam padding
Side view of back panel foam padding

Compression and External Attachment System

The Buttermilks 55 has two tiers of side compression straps that wrap over the side stretch pockets. They work great as long as you don’t store anything hard-sided in the side pockets, but it would be far better if the webbing ran inside the pockets so you can get effective compression when carrying bottles.

Top compression is provided by a single webbing strap that runs over the extension collar and can be used to attach a coil of rope or stiff sleeping pad, like a Therm-a-Rest Z Lite to the top of the backpack.

Boreas Gear Buttermilks 55 Backpack: Recessed Daisy Chains
Recessed Daisy Chains

A pair of recessed daisy chains run down the sides of the shovel pocket that can be used to attach gear to the outside of the pack. These are very clever and tuck away smartly between the shovel pocket and sides of the pack so they don’t catch on anything when not in use or traveling. The daisy chains provide anchor points for the included ice axe shaft holders but can also be used to strap snowshoes or a cylindrical tent body to the outside of the pack…definitely a stand-out feature of this backpack!


The Boreas Gear Buttermilks 55 is an ultralight style backpack that is rugged enough for multi-day backpacking but stylish enough for adventure travel. Featuring a streamlined, functional design, the pack has an excellent suspension system capable of carrying surprisingly heavy loads (up to 35 pounds) without compromising on comfort, function, or convenience. While a bit heavy for pure minimalists, the Buttermilks 55 provides an attractive alternative for hikers or travelers who want one pack for urban and backcountry adventures. Our only caution is to carefully check your torso length and waist sizing when evaluating the Buttermilks 55, because the available sizing is biased towards people with small waistlines.


  • Comfortable padded back panel
  • Recessed daisy chains
  • Attractive color accents
  • Extra heavy-duty pack bottom


  • Top lid does not keep rain from entering main compartment and a rain cover MUST be used
  • Size medium with a 18-20″ torso length is only available for people with a waist size less than 33″
  • Side compression straps cannot be threaded through side pockets only over them

Backpack Features

  • Front mesh stretch pocket
  • Side mesh water bottle pockets
  • Fully integrated hip belt pockets
  • Aluminum wire frame
  • Removable plastic framesheet
  • Internal hydration pocket
  • Draw string closure on main compartment
  • External rear zippered pocket
  • Dual hydration Ports
  • Dual compression straps
  • Ice axe shaft holders and loops
  • Front daisy chains
  • Load lifters
  • Recessed daisy chains
  • Adjustable sternum strap with safety whistle
  • Center haul loop
  • Rain cover included
  • Capacity: 55L/ 3356 cubic inches
  • Weight: 3 pounds 1 ounce on the Section Hiker scale (Size Medium)
  • Removable Framesheet w/aluminum stays: 10.4 ounces

Disclosure: Boreas Gear provided Philip Werner ( with a sample Buttermilks 55 backpack for this review. 

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  1. Looks like a decent backpack, but I have’t seen my belly button in 10 years and I doubt that skinny hip belt is going to fit me! Great review!

  2. I own a Buttermilk and use it mainly for travel without the internal framesheet. I got it in the black color and it really looks great!

  3. I have it’s larger cousin, the Lost Coast 60. Great pack!! After I hike a few miles with it, it conforms very well to my back and hardly know it’s there, even with 25-30 lbs.of gear. The longer I’ve owned it, the more I like it.

  4. This is a nice looking backpack, although concerned about the hip belt. Thanks for the review.

  5. I found this backpack to be a good fit, and I have a 34″ waist. The size is just right for weekend trips, and with a little planning can be used for longer ones. I found the waist/hip belt did a good job of locking into my hips and transferring the weight. The main compartment swallowed all my gear and additional items fit nicely into the stretch panels or else I just strapped them outside. I bought mine on sale from REI, so it was a tremendous deal (IMHO). A great piece of equipment for someone who wants to have an ultralight capable backpack, without paying an ‘ultralight’ premium.

  6. The side compression straps can run thru the side pocket

  7. As Aaron mentioned above, the side straps can run through the pockets in both the buttermilk and lost coast packs. As someone with a 29″ waist, I found this pack perfect. I was dead set on getting a osprey Exos but i tried this pack on. It felt so much lighter due to the great fit. You can cut out nearly a pound by removing the plastic back support and just leaving in the metal frame. I noticed no difference in fit doing this

  8. This is an inspiring review based on the fact that I’ve just ordered this pack and confirms all the points that led me to making that decision. I’m looking forward to putting it through it’s paces. The only thing I noticed, which Aaron has already corrected, is that the compression straps can run through the side pockets.

  9. I purchased this pack about a month ago. I took it on a 4 mile trip, loaded with about 30 lb. It was quite comfortable, and I felt like the lighter weight made a difference. I am 6′-2″ with a 34″ waist and the large size pack works perfect for me. I think it should work up to 36 or 38″ waist just fine. This pack is somewhat smaller than the one it is replacing for me. This will be motivation to pack light to fit everything in (this was the whole idea after all).

  10. I have the buttermilk 55 with the daisy straps. I don’t understand how the daisy straps are used.
    Any suggestions will be appreciated.

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