Guest - Not logged in 

Reviews > Clothing > Jackets and Vests > Montane Flux Mens Jacket > Test Report by Bob Dorenfeld

Montane Flux Jacket
Test Series By Bob Dorenfeld
Initial Review    November 22, 2013
Field Report    February 11, 2014
Long Term Report   April 2, 2014

Tester Bio
Name: Bob Dorenfeld

I'm an active hiker, snowshoer, skier, backpacker, amateur geographer and naturalist.  Home base for me is the Southern Colorado Rockies, where I'll hike from 7000 ft (2100 m) to above treeline, with an occasional desert trip to lower altitudes.  Six to 12 miles (10 to 20 km) in a day is my norm, including elevation gains up to 4000 ft (1200 m).  Most of my backpack trips are two or three nights, sometimes longer, carrying 30-40 lbs (14-18 kg).  My style is lightweight but not obsessively so - extras like binoculars, camera and notebook make my trips more enjoyable.

Email: geartest(at)sageandspruce(dot)net
Age: 55
Location: Salida, Colorado, USA
Gender: M
Height: 5' 6" (1.68 m)
Weight: 135 lb (61 kg)

Product Overview

Manufacturer:    Montane
MSRP:    GBT£140.00  (US$.227.00 at the time of this writing)
Size:    Men's Small
Measured Weight:    18 oz (512 g)
Color:    "Steel" (dark gray) with orange zippers, lining, and pull cords
Other colors and sizes:    Several other color combinations are available, will vary by retailer; sizes are S, M, L, XL, XXL (men's)

 Montane Flux Jacket
Photo:  Montane
The Montane Flux is a very lightweight jacket from a British manufacturer with an outer layer of Pertex® Microlight rip-stop surrounding an insulting layer of Primaloft® ECO.  (Primaloft synthetic insulation was produced originally for the U.S. Army, and is now a popular synthetic substitute for natural down.)  The jacket is designed to sit firmly against the torso to provide warmth, but also allow enough room for active sports without binding.  It has two hand pockets and two breast pockets, all with plastic one-way zippers.  There is also an inside breast pocket on the right side.  The front zipper is two-way, with the zipper pull on the left side, a European convention opposite from the American preference on the right side for male clothing.  An elasticized cord at the bottom hem with a cord lock on either side, plus an optional plastic snap, draws the jacket tight around the waist if desired.  Hook and loop closures seal the sleeves tightly against the wrists.  The permanently attached hood can roll back when not needed, secured by a wide hook and loop strap.  Three elasticized cords allow for fine-tuning the hood fit - one at the back of the neck, and two at the front along the collarbone.  In addition, the hood brim edge is adjustable via an embedded stiff wire.

- Initial Review -

First Impressions     

I'm first struck by how light this jacket is - by far the lightest I've owned for its expected insulating value; but compared to good-quality down the insulation does not have much loft and thus the jacket is slim.  As I try the Flux on for the first time (men's small on my 38 in (97 cm) chest), I take note if the sleeves fit my arms well, how tight or loose it fits against my torso, and if the hood surrounds my head well and can be adjusted without too much fussing around.  It's got a very silky-smooth feel on the outside.  Except for a slightly longer sleeve than I would prefer, I like the fit in all these areas when I wear it around the house for the first time.  All of the zippers were easily operated and ran smoothly.  For a winter jacket it feels a bit thin as I noted above, but then this my first experience with Primaloft®, so I'm really looking forward to putting it to the test in the field.  It's very comfortable, allowing easy movement of my arms all around.  When I zip all the way up the first thing I notice is how it nicely covers my chin - and snugly too; after slipping the hood up around my head, it fits snugly all around.  Pulling the hood's three shock cords tight to really close it up, I noticed the stiff-wire adjustable brim - a nice touch.  Since the Flux's hood is not detachable, there is a hook and loop flap that secures it in place after being rolled up.  All of the pockets are generously-sized, especially the inner breast pocket on the right side.  The entire jacket is designed to be stuffable into the right-hand pocket - and indeed I was able to do so in under three minutes without too much trouble, making final package not much larger than a one-liter water bottle.

- Field Report  [February 11, 2014] -


I've been busy in the past two months field testing the Flux jacket as our Rocky Mountain winter settles in with deep snow and cold temperatures.  In all, I accomplished eleven hikes for about 40 mi (64 km), one afternoon of light bouldering, seven snowshoe treks for about 30 mi (48 km), three Nordic ski trips for 8 mi (13 km), and one all-day alpine ski outing.  In all, I experienced temperatures from 0 to 40 F (-18 to 4 C), and wind chills as low as -50 F (-46 C). On most of the outings I wore the Flux jacket with only a wool-blend long-sleeve shirt underneath.  The exceptions were two trips when temperatures reached a high of just 15 F (-9 C), and I needed a lightweight fleece over my shirt and under the jacket.  In addition to the usual dry and cold Colorado environment I had the opportunity to wear the Flux in rainy, humid Texas.

Fit & Performance

As I noted in First Impressions (above), the Flux fits me quite well overall - small was the correct size for me.  After using it a couple of times, I found that I liked to snug up the bottom at my waist using the shock cords: this helps keep warm air in, so I leave it adjusted that way most of the time.  However, the jacket is cut with a slight "apron" at the rear, which helps cover pant tops where a shirt might be tucked in; this is useful when the hem is not tightened via the shock cords.  Sleeve length is just a bit long for me with the cuffs loose, but I leave the hook-and-loop cuff tighteners set in place so that they are snug enough, but with enough room for my hands to slip in and out of the sleeves.Front

My favorite feature of the Flux has to be the collar and hood design - I've never had a winter jacket where I actually wanted to zip up all way to keep the hood pulled up and almost forget to notice that it's up!  The front of the collar is lined with polyester fleece to feel soft, but more importantly, the fabric lays snug against my neck and chin without binding or letting in too much cold air.  The two orange elastic cords on the front sides of the collar help keep it adjusted exactly where I need it - tight when the cold wind blows, looser when I need more air circulation.  Also, I rarely felt any binding on the collar when turning my head.

Hood tight

The same goes for the hood - it wraps very well around my head, and in addition to the side cords for the collar, a third orange elastic cord at the backside (above the neck) pulls the hood tight around the sides and top of my head.  Like the collar, the hood stays in place even when moving my head side to side, without disturbing position of the hood top or opening my neck to the breeze, and the adjustable brim stayed where I put it.  Since I wear glasses all the time, I was initially concerned that too much wind would slip in around the sides where the hood can't cover the glasses' temples, but this turned out to be not an issue when I pulled the hood just a bit tighter.  Being able to keep good peripheral vision is especially important in area alpine skiing when the slopes are crowded, and this hood performed above my expectations in this regard.  And, as a bonus, I found that the hood fit very nicely over my medium-thick brim-style hat, giving me a bit more sun protection than the Flux hood alone.  Although the hood rolls up and can be held in place by a hook-and-loop strap, after about my third outing I found it easier to just leave the hood hanging loose when not needed; but when rolled up, it was not in the way and merely made for a slightly thicker rear collar.  I observed that the jacket's hanger loop is not available when the hood is rolled and secured by the hook-and-loop strap; a minor design flaw that could be remedied.

So, is the Flux warm?  You bet!  Wearing only a lightweight wool-blend long-sleeve shirt underneath, the Flux obviated my need for the extra fleece that I usually pack for backup.  In fact, when exerting strenuously while breaking trail on snowshoes or Nordic skis I ended up with a pretty good sweat, so I regulated my temperature by opening the front zipper from the top either halfway or 3/4 of the way down.  Although there were a couple of outings where the temperature warmed up to freezing and the Flux just seemed too warm overall, I was glad I had it on when stopping for a rest, because it let me warm back up rather quickly.  As far as wicking damp air from my core, the inner lining of the Flux (which Montane calls "PEAQ Synthetic") didn't do as good a job as I expected, and this is in a very dry winter climate with relative humidity around 40% or lower.  After one particularly strenuous snowshoe, the entire lining was almost dripping wet, and my wallet in the inner pocket was damp as well.

I had one opportunity to test the Flux in relatively warm, wet weather (over 40 F (4 C)) in humid Texas, and I was impressed with its water repellency in a light-to-heavy rain during a two-hour walk.  Unlike some of my Colorado hikes, I didn't feel clammy (despite the humid air), but this is probably because the walk wasn't very strenuous.  However, in all of my test outings, regardless of temperature or climate, the outer ripstop fabric did very well against the wind, and I never felt the need to layer on another windbreaker over the Flux.

As far as jacket flexibility and movement, I like how comfortable the Flux is while skiing both Nordic and alpine style.  I didn't feel any binding in the arms or waist - the articulated arm design is successful. In addition, for these activities I appreciated the relatively thin jacket filling (especially when compared to a puffy, and sometimes bulky, down jacket). Side

Did the pockets live up to initial expectations?  With one exception, yes.  The two "Napoleon-style" outside breast pockets are very generously-sized, and in them I would store a glasses case, trail snacks, extra grove liners: just about anything small that I'd need quickly while on the trail.  The smaller inside-breast pocket, on the right side, was convenient for my thin or small items (like a wallet or keys) that I didn't need to get to very often.  I like the hand pockets for their size and placement:  As Montane mentions in the jacket specifications, they are designed to be out of the way of backpack straps, thus I could use them anytime.  (On the other hand, comparing this jacket to other jackets that I own didn't show any significant differences in hand pocket placement - all were as comfortable as the Flux with a pack.)  In the photo to the right I've have three pockets stuffed with mittens and some other gear - looks funny but stores well!  All four of the exterior pockets are reinforced at their top ends where the zippers close up - nice attention to detail.  My one gripe about the hand pockets is that they are not lined with fleece material, and the nylon ripstop lining (same as the jackets outside) sometimes felt cold and clammy on my hands.

All of the jacket's zippers worked flawlessly, and I'm hard put to remember any time that the front zipper caught in the fabric - always a clothing hazard.  Although there are no fabric zipper covers on the jacket's outside, the front zipper does have a 0.8 in (2 cm) thick insulated weather strip sewn in behind the right-hand zipper side, which does keep wind and wind-blown snow from migrating inside the jacket.  According to British convention (Montane is based in England) the front zipper is "left-hand", with the pulls on the left side, but I quickly got used to reversing my hands when using the Flux's zipper.

In regards to the thin outer shell ripstop nylon, I initially had some reservations about how well it would hold up against off-trail obstacles like tree branches and rough rocks.  However, experience so far has shown that the shell nylon is quite durable, holding up to mild rock abrasion, small twigs and branches, and non-thorny brush.  One afternoon of some light bouldering on rough-surfaced limestone and rhyolite left some dirt and other marks that came off easily with water and light rubbing.



Montane has thoughtfully designed a self-storage feature in the right-side hand pocket's lining, which pulls out to allow the rest of the jacket to be stuffed into it.  It took me about one minute to complete the task, and it was pretty easy to push the jacket's fabric and stuffing into the pocket and the corners. 

I was careful with the wire in the hood brim so that it didn't get bent too much out of shape.  I noted that there is reinforced stitching at both ends of the now-exposed pocket zipper, which will help when it's stressed slightly in order to zip up the bag with the jacket inside.  I used this storage feature only once so far on my winter trips, because I kept the jacket on and didn't need to store it.

Loose Thread Issue

stray thread with arrow

I had only one problem with jacket workmanship, and it was a minor one at that.  A thread had pulled out at the bottom of the right-side breast pocket, to about 0.5 in (1.3 cm).  It proved to be an easy fix with a needle and short length of gray thread as I tied it off and tucked it back in securely.  However, I don't consider this a serious problem (I've seen loose threads many a time on outdoor gear) and I usually find loose threads easy to repair, as it was here.


After two months of extensive use, my evaluation so far of Montane's Flux jacket is very positive.  For me it's living up to Montane's claims of comfort, warmth, flexibility during strenuous activity, ease of use, light weight, and wind- and waterproofness.  It has become my outdoor winter jacket of choice, replacing the two-layer combination of fleece and hard shell that I used to wear during winter hikes, snowshoes, and skis.  A note on color: the dark gray and vermilion combination seen here was not my first choice, and at first I didn't like it.  But after wearing the Flux a lot, the bright orange of the zippers and inner lining bothers me less, so that form and function is more important to me now.

- Long Term Report  [April 2, 2014] -

Since my Field Report (above) was posted I've continued to use the Flux jacket on about five hiking and snowshoe day trips 6 mi (10 km) or greater, as well as shorter walks around town, where temperatures varied from 20 to 50 F (-7 to 10 C).  I still think it's a great jacket, for all of the reasons I give in the Field Report.  I've not seen any additional loose threads or, indeed, any other defects.  I'm going to add the Flux to my spring-through-fall seasonal backpacking gear as well, because even then in the high mountains of Colorado it frequently drops to freezing or below at night.  A brief test at home indicates that the jacket will also make a good camp pillow due to its excellent loft.  Finally, this is definitely a winter or cold-temperature jacket; being active in the Flux at or above 40 F (4 C) was too warm for me, and there is no ventilation other than at the sleeves or by opening the front zipper.

I have only a couple of minor negative design observations about the Flux, but in my opinion neither of them detract from its overall excellent design and comfort.  The first is that the hanger loop attached to the inner side of the collar is unavailable when the collar is rolled up and its hook-and-loop strap is fixed in place.  This could easily be fixed by placing the hanger loop just below the hood strap instead of above, where it is now.  Second, the breast pockets are too big for me - that is, they bottom out into the tops of the hand pockets, so that when I store an item like my sunglasses case in either breast pocket, that item gets into the way of my hand when using the corresponding hand pocket.  I would have these pockets bottom out about 2 in (5 cm) higher than they do now.

  • warm and snug
  • excellent hood fit and coverage 
  • very compressible & very lightweight
  • water repellent
  • 5 pockets provide lots of storage space
  • adjustable cuffs and waist
  • very adjustable hood fit, with stiff visor wire
  • excellent flexibility in hood, shoulders, and arms
  • hanger loop not available when hood is rolled up
  • breast pockets too large, stored items can sometimes interfere with use of hand pockets


  A big thanks to BGT and to Montane for the chance to test and evaluate the Flux winter jacket.

Reviewed By
Bob Dorenfeld
Central Colorado Mountains

Read more gear reviews by Bob Dorenfeld

Reviews > Clothing > Jackets and Vests > Montane Flux Mens Jacket > Test Report by Bob Dorenfeld

Product tested and reviewed in each Formal Test Report has been provided free of charge by the manufacturer to Upon completion of the Test Series the writer is permitted to keep the product. Owner Reviews are based on product owned by the reviewer personally unless otherwise noted.

All material on this site is the exclusive property of
BackpackGearTest software copyright David Anderson