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  • Arc'teryx - Alpha FL 45L Backpack - Cardinal
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  • Arc'teryx - Alpha FL 45L Backpack - Cardinal
  • Arc'teryx - Alpha FL 45L Backpack - Black

Arc'teryx Alpha FL 45L Backpack


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    4 Reviews


    For fast and light alpine missions.

    The ultralight and highly weather-resistant Arc'teryx Alpha FL 45 Backpack is designed to help you move quickly through rugged terrain whether you're on a light alpine mission, crushing ice and rock climbing, or putting in technical ski mountaineering lines.

    Arc'teryx made the Alpha FL from lightweight but bomber ripstop fabrics to withstand the rigors of ice and granite without slowing you down. To keep your back and shoulders comfortable, the AC2 suspension system offers load support with minimal weight, while compression straps help you manage your load for better balance in tricky spots. The Alpha FL is also fitted with an expandable drawcord collar for additional capacity on a minimalist overnight trip. External attachment points can be used to hold skis or a sleeping pad, and a front panel bungee attachment stashes crampons or an extra layer so you don't have to stop any unpack every time you move from flat ground to steep snow or ice. The webbing hip belt is lighter than padded belts and fits more comfortably under a harness, and thermoformed shoulder straps and a rigid formed backpanel provide support and structure while still offering a comfortable fit.

    • HyPUR-cel foam straps
    • HD 80 foam back panel
    • AC2 suspension system
    • Fully sealed seams
    • Roll-top closure
    • WaterTight external zippers
    • Six front lash points and bungee front attachment system
    • Webbing hip belt and removable sternum strap
    • Extendable collar for additional capacity
    • Item #ARC00HS

    Tech Specs

    N400r-AC2 nylon 6 ripstop, N100mr-HT nylon mini ripstop, N70r-HT nylon, HyPUR-cel foam, [back panel] HD 80 polyethylene foam
    45L (2746cu in)
    AC2 system
    Shoulder Straps
    400D AC² nylon ripstop, Burly Double Weave foam, Hypercell foam
    Waist Belt
    yes, 40mm nylon webbing
    1 main compartment, 1 security zip
    Gear Loops
    Ice Axe Carry
    Claimed Weight
    1lb 7oz
    Recommended Use
    alpine & expedition, climbing
    Manufacturer Warranty

    Tech Specs

    • Reviews
    • Q & A

    What do you think about this product?

    Have questions about this product?

    Beauty in Simplicity

    • Familiarity: I've used it several times

    This bag is simple, straight-forward, and bomber. It only has one compartment, but if you pack well, it's not an issue. I love the expandable drawstring system at the top, too. I was pleasantly surprised by how comfortable it was when weighed down with gear, as well as how balanced it felt when walking. Overall an awesome, simple pack for any winter adventures that will last for years. 10/10 would recommend.

    The best

    • Familiarity: I've put it through the wringer

    I love this pack and everything about it.

    I have used this pack for both technical purposes (i.e., climbing and hiking) as well as just basic commuter/daily purposes and I find it works great for both. However, it clearly is designed, and excels the most, in the alpine environment.

    (1) The pack is amazingly lightweight for its size (there is a caveat to the size I will mention later).
    (2) It is incredibly durable and water proof. I personally have yet to tear a hole into this pack or managed to have any water permeate it whatsoever.
    (3) Simplistic design with just enough support in its frame and straps
    (4) The design allows it to hold tightly to your body, which is incredibly important in a pack while climbing.
    (5) Easy to manipulate (i.e., open the main and external compartments, put on/take off, adjust straps, unclip waistbelt) in the freezing cold while wearing multiple layers of gloves. Hell, although I haven’t tried, you could probably do everything you need to even with mittens on.
    (6) Ice axe/tool attachments are easier to use than traditional attachments
    (7) Crampon straps work great. I thought my crampons would have cut these by now, but I have yet to have any issues. Also, you can use the straps for other things you need to attach on the outside (e.g., helmet, belay jacket)
    (8) I actually find the key hook in the external pocket quite useful most of the time. That said, I am not carrying my house keys on me for big alpine objectives and haven’t found a use for it then.
    (9) The external attachment points on the Alpha FL 45 (do not exist on the 30L model) are very useful, particularly for attaching boots for approaches.

    (1) Expensive, but it find it is worth it
    (2) The size is a bit deceiving, as the size in the name of the product is actually the size with the roll top fully expanded.

    Best skimo backpack

    • Familiarity: I've put it through the wringer

    The simplicity is the greatest thing about this pack. After two seasons I've used this pack for a litany of missions, but ski mountaineering has been the best application. Pack intelligently and there's nothing better.
    The white interior makes a bigger difference than you'd think and the shoulder straps are way more comfortable than they should be. I couldn't be happier.

    Best skimo backpack

    Lightweight, but doesn't carry skis well

    • Familiarity: I've put it through the wringer

    I have mixed feelings about the Arc'teryx Alpha FL 45 backpack.

    The Pluses:

    * It is crazy light! The lack of padding on the waist belt and should straps doesn't affect the comfort.

    * The material is bomber-strong. Arc'teryx-strong!

    * It rides close to my back which gives it an extremely balanced feel. The balance is enhanced due to its tall-and-skinny profile.

    The Neutrals:

    * There is only one compartment. Duh! That'€™s due to its weight-saving design. I use three ultralight stuff sacks to organize my gear within the pack which worked well. However, I now know I would prefer one or two simple compartments even if it adds a little weight.

    * There isn't a dedicated avalanche rescue gear compartment--again, for weight savings. I had a friend make a small (light) sack to keep my three avy items together. On my next pack, however, I'll return to a dedicated compartment.

    * It's 35 liters and 45 liters when the collar is extended. I knew that when I purchased it and am pleased with its size, but just in case YOU are thinking it is 45 liters...

    The Minuses:

    * It doesn't carry skis well. This is a big issue for me. Before buying the pack from, I wrote Arc'teryx asking if they sold ski straps. They told me to use any strap. But it isn't so easy: the loops on the back of the pack have tiny loops (2-3 mm), so I had to tie into the loops using 2-3 mm cord. The loops on the sides of the pack were also quite small. I had four straps made from 5/8-inch€ webbing. Although time consuming, when I was done the straps were very functional. However, the third time I mounted my skis, one of the backpack's side loops pulled out from the stitching (and FWIW, I was carrying ridiculously light Dynafit Denali skis). Deep in the French Alps, I had to puncture the pack with my knife and repair the loop with a zip tie. graciously warrantied the pack and I think it was a manufacturing defect rather than a design defect (the other three straps held up to repeated ski carrying), but the bottom line is, between the complexities of making the straps and the failure of a pack loop, I don't recommend this pack to carry skis.

    * The ice axe thingies (the T's on the elasitc) are a good idea, but they don't cover axe's pick and aren't very secure (I lost an axe...).

    * Occasionally my scapulas (aka shoulder blades) are slightly uncomfortable due to the lack of padding on the back. This is minor.

    My Use:

    I used the Arc'teryx Alpha FL 45 backpack for 30+ days of backcountry skiing, including a six-day hut trip in Europe. I've owned a half-dozen different ski touring backpacks over the last 20 years. My most recent backpack before this was a Black Diamond Anarchist.

    Lightweight, but doesn't carry skis well

    Solid review and helped me decide on purchasing, thanks! Also, clever ski attachment strap rig you did there. I could be wrong but I think they intended the middle lash point (with the larger aperture) to be the one used for the ski straps. Using a single piece of flat webbing, with a ladder lock to tighten it, this creates a zig-zag configuration going from the top lash point near your body, to the middle point on the pack's back, then back to the lower point near your body. Kind of a mirror image of what you'd find OEM on an Osprey Talon. Seems pretty stable so far, if the bindings are properly snared, but I haven't field tested. Time will tell. Cheers!

    I appreciate the comment. I was about to buy one of these but the size comment is what swayed me elsewhere. I wish they'd market the size more like Deuter using a plus sign (e.g. 35+10).

    You can actually just stick a ski strip through the loops. In this picture, the strap would go through the right loop, not the left one. Fits snuggly.
    Not sure what the problem with ice axes is. When I have my axes on the pack, I put the picks underneath the bungee cord to keep them from moving at all. Have never lost anything, and this pack has taken my to Chamonix, Patagonia, Cascades, Canada. Just saying ;)