The Rab Alpha Flux Jacket is lightweight, has a small pack size and is extremely cuddly thanks to the soft fabrics. Read the review and watch the video!
- Price: € 140.00
- Weight: 348 grams (S)
- Sizes: S, M. L, XL, XXL and ladies UK 8 to 16
This review (and the video) was made a 2018 and by now the Rab Alpha Flux Jacket has been updated. I have updated my wardrobe also to the new version and I still stand behind everything I write in this review except for one thing: the outer material has changed to a more durable nylon that makes the jacket even tougher making the Alpha Flux to one of my all time gear favorites.
The Rab Alpha Flux Jacket is a fleece jacket with a hood. You can wear it as an outer layer from spring to autumn and as an insulating middle layer in the winter. I am testing the men’s version here, but there is also a women’s version. The jacket consists of different materials and layers and that deserves explanation.
The red panels of the jacket consist of an outer layer of 100% polyester (new version Nylon) with the insulating layer behind it. This insulation layer is made from Polartec Alpha. Polartec Alpha is a fleece-like material of 100% polyester. The core is a fabric of very open fibers. Due to this open structure, Polartec Alpha is able to retain a lot of warm air and thus insulate it. But there is also something special about those fibers: they are hydrophobic.
Hydrophobic fibers have the property that they themselves do not or hardly retain moisture. I have done a few tests with it and for that I best refer to the video. In testing, I compared Polartec Alpha with thin cotton and with thick cotton towels (same size of course) and found that Polertec Alpha has only a 63% weight gain while the thin t-shirt and towel showed a 240% weight gain. Less wet means a faster drying time. And you need less energy to heat that little bit of wet weather dry, saving you energy that you can use for your activity to keep warm. Polartec claims that the material even does its job better as your effort increases and you sweat more. How is that possible? No idea!
Rab Alpha Flux Jacket Thermic-lux
As mentioned, not the entire jacket is made of Polartec Alpha. The purplish panels are made of a thin super stretchy ‘Thermic-lux’ fleece material. A material consisting of 94% polyamide and 6% elastane. The latter material is elastic and that gives freedom of movement. The entire jacket has been treated with Polygiene Stay Fresh to combat body odors. And if it starts to smell anyway: washing at 40 degrees in the washing machine and putting it in the dryer at the lowest heat is allowed.
The fit is sporty tight, so I didn’t suffer from flubbing pieces of fabric. Something that I find really annoying if you wear a fleece as an intermediate layer under a hardshell, for example. The back is longer than the front. The back covers not only the lower back but also the topside of your bum. I like it, because now I never get a cold back if I have to tighten my laces. Many fleece jackets have an adjustable elastic around the hips. The Rab Alpha Flux Jacket doesn’t need this: the material is so stretchy that the jacket will close anyway.
Cuffs with thumb holes
The sleeves of the Rab Alpha Flux Jacket are relatively long and have holes where your thumb can stab through. Another plus because, for example, you never get bare forearms when stretching out all the way on a via ferrata. In addition, those cuffs with thumb holes also help to keep your hands (partly) warm.
Collar and hood
The collar of the Rab Alpha Flux Jacket is high and closes perfectly. The zipper has a zip garage so you don’t feel it against your throat. With the hood down you have quite a bit of fabric around the neck and you have to like that. If you wear another jacket over the Rab Alpha Flux Jacket, this can play tricks on you.
The hood itself is very nice in colder weather. Although it has no adjustment options, it still closes well all around my head. Especially around the back of the head it fits nicely, which is nice if you wear a helmet over it. The hood and collar do not restrict freedom of movement. That the hood does not have a flap, does not bother me. A flap also would not – strangely enough – really fit the character of the jacket.
The jacket has zippers from zipper giant YKK: one at the front and two at the pockets. The zipper at the front cannot be opened at the bottom when closed. It does have a good pull cord so that it can also be operated with cold hands or gloves. Behind the front zipper is a draft strip that also prevents the zipper from accidentally getting stuck in the fabric. The zippers all run smoothly.
The two pockets are of generous dimensions and an Iphone 8 Plus fits well in it, as well as a topographic map. The pockets are in exactly the right place: even with a backpack they are easily accessible, and you can put your hands in the pockets to warm them up.
The Rab Alpha Flux Jacket feels like a kitten’s belly on the inside: terribly soft and cuddly. Despite its tight fit, I have a lot of freedom of movement. Some fleeces are so thick that they give resistance to wear. The Rab Alpha Flux Jacket can also be worn comfortably under a hardshell or as an extra layer under a down jacket like the Rab Microlight Alpine Jacket that I reviewed for the real cold days.
The Rab Alpha Flux Jacket is highly breathable. This becomes evident when I do not get very wet during a heavy work-out. It is therefore important that the layer you wear underneath does not retain moisture. Cotton is a no-go! I also notice that Polartec Alpha hardly retains moisture. The Polygiene anti-odor treatment works as far as I can judge: after four weeks of intensive wear I still dare to go into a full cinema!
Wind has free play
The high breathability also has another property: wind has free play. So you shouldn’t think that the Rab Alpha Flux Jacket looks anything like a softshell – more on softshell jacket here – or a windblocker. During colder and windier weather it is important that you bring a layer that can block the wind.Otherwise you will cool down during a stop real quickly. You also need that layer when it rains, because the Rab Alpha Flux Jacket is far from water resistant. During testing, I noticed that the Polartec Alpha material is sensitive to twigs, thorns and other choppy hooks. I soon had a few loose loops. Not a jacket to romp through dense thickets.
The Rab Alpha Flux Jacket is by now my second home. And I know since I bought a few the last couple of years. The comfort is super, and the pockets are practical in combination with a backpack. Polartec Alpha has proven to be warm, has a super breathability and remains odorless thanks to the Polygiene treatment. The jacket is lightweight and compact to pack. Comparing the old polyester fabric to the new nylon: the old one is sensitive too twigs and rubbing but the new nylon version is much better. The jacket is neither windproof nor water-repellent. So take an extra outer layer with you when you pause for lunch on your hike. I think the Rab Alpha Flux Jacket is so good that it should not be missing in any outdoor wardrobe: 9 out of 10 points!