#Note: Find full Arc'teryx review list at the bottom.
Dually Belay Parka is the warmest synthetic insulated piece in the Arc'teryx line-up. It's also the 3rd warmest in Arc'teryx's entire insulated jacket family (excluding this monster from Arc'teryx LEAF, as its "too technical").
Dually Belay is also my top Arc'teryx pick for extreme colds, as you can see here: https://outdoorcrunch.com/best-arcteryx-jacket/
First thing you should know about Dually Belay is that it's stupid warm.
It's equipped with ThermaTek (exclusive to Arc'teryx), which provides a superior insulation capability than other insulation filaments such as the Coreloft.
Not only the insulation filament used in Dually Belay is premium, but also the amount of this insulation is generous (92 g/m²).
And even this is not the end point for this parka in terms warmth.
In addition to all these, The abundant insulation material used in the Dually Belay is spread through not one but two layers.
If you're familiar with my post about the working principles of insulated jackets, then you already know that this is a huge advantage for warmth. Because the air trapped in between the layers is also leveraged to work as an extra layer of insulation.
Find below the lowest temperatures you can wear each jacket without feeling uncomfortably cold.
These are only approximate values assuming:
- you only have a shirt under and no shell over,
- during daily use (strolls, power walks etc at most - no high output activities),
- with light wind,
- and when it's dry out.
°F / °C
Arc'teryx LEAF Cold WX Parka SVX (Men's)
Arc'teryx Ceres SV (Men's)
Arc'teryx Dually Belay Parka (Men's)
Arc'teryx Thorsen Parka (Men's)
Arc'teryx Centrale (Women's)
Arc'teryx Therme Parka (Men's)
Arc'teryx Camosun Parka (Men's)
Arc'teryx Patera Parka (Women's)
Arc'teryx Kappa (Men's)
Arc'teryx Magnus Coat (Men's)
If you think you run warmer or colder than the average person, then shift these temperature ranges accordingly.
I've also put together an Arc'teryx spreadsheet recently. Might help you out:
If you paid enough attention to your Thermodynamics class in school, then you already know what I'm talking about. Air makes up a perfect insulation material.
Being able to trap air between the two layers, Dually Belay leverages this very advantage of using the air as extra insulation. An important advantage which (to my knowledge) no other jacket can achieve on their own due to their single layered structure.
One of the most important upsides to layering is the advantage of being able to trap air between the layers, have that air heated by your body, and ultimately leverage that air as extra insulation.
This is a great extra warmth with no costs (such as extra weight).
Dually Belay is... WARM. Mind you, though, if you're like most people, for temperatures over 10 deg F (-12 deg C), it can even be TOO WARM for most of you!
Dually Belay is equipped with 30 denier nylon face fabric. This is quite a bit wind and water proof, although not as waterproof as another similar Arc'teryx jacket Fission SV (more on this later).
It's one of very few Arc'teryx jackets made in outside Asia.
See the manufacturing locations for all Arc'teryx jackets here: https://outdoorcrunch.com/where-is-arcteryx-made/
Dually Belay is also DWR coated.
DWR is a coating.
It's basically sprayed on to the surface of these jackets as a finish. It stands for Durable Water Repellent - which means that water will be repelled under wet conditions instead of soaking into the fabric.
DWR also decreases dry time.
It's a good thing these jackets are coated in DWR, but pay attention to the fact that DWR is a coating - meaning that it will wear off over time.
Which is why you might want to invest in a DWR spray such as this one for after treatment.
As you see, there's a strong correlation between FP x FW and temperature ratings, but not more than, say, 80%. I explained why this happens here in this post of mine.
In summary, I'd highly doubt you'll experience any problems in terms of water and wind resistance inside this jacket. Synthetic insulated jackets are known for being very resistant to wet weather conditions.
I evaluated Fission SV's temperature rating as well, and found it to be 3 deg F (-16 deg C). Whereas that of Dually Belay is lower at -7 deg F (-22 deg C), as mentioned earlier in this post.
As you see, Fission SV still very warm, though it isn't as warm as Dually Belay.
Now although the Fission SV isn't as warm as the Dually Belay (as you see), it does get ahead of Dually Belay in one department: Waterproofing. Fission SV is noticeably more waterproof than the Dually Belay.
In fact, it's the warmest fully waterproof Arc'teryx jacket.
Another advantage of Fission SV is that it's also offered in women's specific counterpart, unlike Dually Belay which is only offered for men.
Here's the product video for Dually Belay Parka: