Montane Flux Jacket – a well featured piece of synthetic insulation for year round belay duties.
Value for money *****
RRP Jacket £130.00
These days many companies produce what they call a “belay jacket”. Something you can throw on over the top of your other layers on long winter belay stints or when holding your mate’s ropes for hours when he’s dogging his sport project. They’re also great as a bivi back-up and can even be regularly seen posing down the local pub. For UK use the most favorable filling is some sort of synthetic insulation such as Primaloft or similar. This means that even if it gets wet or damp it won’t lose any of it’s insulating capacity.
I’ve tried a lot of synthetic belay jackets over the last few years and have found, like with everything else, that some are better than others. I normally look for certain essential features. These are:
- helmet compatible, insulated hood
- adjustable cuffs (makes it easier to get on and off over layers)
- two big handwarmer pockets
- two way zipper (means you can pull it down to cover your upper bum and hips but still access your belay loop)
- mesh internal pockets
- cut large enough to go over the top of your base, mid and outer layers
- athletic enough to climb in if need be
So, does the Flux Jacket provide decent cold weather protection? The microlight Pertex outer is windproof and coupled with a DWR finish, repels light moisture well. It dries quickly when damp and is also proving to be quite tough. The layered 60g/40g Primaloft synthetic insulation provides great warmth for it’s weight. I was a little confused regarding the layout of the insulation so I asked Montane to explain things further:
“The arrangement of 60g and 40g is as follows:
· 60g in the back
· 60g in the crown of the hood
· 40g in the sides of the hood
· 60g in the arms
· 40g in the cuff area
· 2 layers of 40g in the chest area, meaning that the front pockets are encased between these layers.”
The idea is that the thicker insulation is sited in key areas where warmth is needed most, such as the core and the lighter insulation is used elsewhere. This works really well and gives a jacket that is warm, pretty light and offers excellent mobility when on the move.
It’s not as warm as say a Patagonia DAS Parka, but then again with the Flux weighing in at 540g for a Medium, the DAS Parka is 250g heavier. Having used the Flux jacket as a belay jacket this winter in both Scotland and on day routes in the Alps I have found it to provide more than enough warmth. It certainly sits happily alongside other synthetic belay jackets of a similar spec such as The North Face Redpoint Optimus or RAB Generator Alpine jacket, providing a good level of warmth to weight. If I was going to be spending nights bivvying in the Alps in winter however, then maybe I’d opt for something warmer (and probably filled with down).