We so often hear of revolutionary new fabrics, boasting impressive stats on performance and breathability, that it's hard not to be cynical. So when we first heard about the Kinetic Alpine Jacket and Pants (trousers) it was their real world performance that interested us more than the on-paper claims. To get a real feel for how this stuff works out there, we spent several months putting it through its paces. And we're really impressed with its unusual combination of a softshell-like breathability and comfort, but with the waterproofness of a hard shell. On a day of mixed mountain weather, this could be all the waterproof you need.

In Use

For the first couple of months we had the Kinetic Alpine we were faced with an unusual issue: it didn't rain. Given that we were in the process of reviewing a waterproof this was clearly something of an issue, but then again this is no ordinary waterproof. This stuff looks and feels much more like a softshell than the crinkly hard shell you might expect, only with an actual membrane and taped seams to give it that waterproof performance. Is this the best of both worlds?

The plus side of all the dry weather was that it did allow us to test the jacket's breathability. Whilst walking, especially on dry days, you barely notice the sweat building up due to the jacket's level of breathability. Whilst running, which is clearly the next level in terms of output/exertion, the Kinetic Alpine manages to pick up the pace. Clearly there's got to be a catch, but we'll come onto the fabric's waterproofing capabilities a little later.

In terms of the jacket's intended use, whilst it's Alpine by name it's actually a whole lot more versatile by nature. I could easily see hillwalkers, climbers, scramblers and fell runners carrying this as a 'just in case' piece throughout the spring/summer months. It's light enough, and versatile enough, to be one of those things you'd pack without too much further thought and may even replace the wind shirt or light softshell for some people.

Fit and Cut

Both jacket and trousers come in men's and women's fit - and it's great to see female users not having to settle for a less technical alternative.

Rab categorise the fit of the Kinetic Alpine as 'slim', which is an accurate description. That said, it doesn't feel too narrow, being a well tailored design, and broad enough across the shoulders. Even though it's pretty minimalist I've found it doesn't lift whatsoever whilst raising my arms above my head.

My only real gripe with the cut is the arms, which - at least in my opinion - could do with another inch or two in length. Whether this is because I have particularly long arms, or because my needs are fundamentally more climbing based, is up for discussion, but it's the only aspect of design that I could call into question.

Fabric

Rab's 'Proflex' technology is quite a fascinating one, insofar as it's a product with a distinct priority: breathability. When it comes to waterproofing it has a hydrostatic head of 10,000mm compared to Gore-Tex Pro Shell's 30,000mm. Whether or not you know what these figures mean is actually not all that necessary, I've just included them as an indication that this isn't necessarily the jacket you'd use for more prolonged use in persistent wet weather. This is a jacket you'd be more likely to use in lighter or more sporadic rain, on a day of sunshine and showers perhaps.

When it comes to breathability, Proflex features a MVTR (moisture vapour transmission rate) of 35,000mm/sqm/24hr, compared to Gore Tex Pro's 25,000mm/sqm/24hr. Once again, understanding the figures isn't necessarily key, but what is important is the difference between the two: Proflex is far far more than just an 'own brand' material. The rate at which it can get that water vapour (i.e. sweat) out of the jacket really is quite remarkable, both on paper and in practise.

Its nylon face fabric will resist abrasion better than polyester. In order to increase the durability on the jacket and pants, Rab have used a ceramic print to bolster areas of high wear such as the arms and shoulders. The reason for using a print, as opposed to something a little more integrated, is that it doesn't interfere with the properties of the material itself, such as the stretch. Whilst I haven't personally had any problems with wear and tear, I don't think this finish is going to help prevent major tears, instead it would likely provide a bit of protection from the odd scuff; as with all lightweight jackets, the Kinetic Alpine isn't going to be as durable as a mid-heavyweight alternative.

One final observation about the fabric is the noise, or the lack of it. Proflex is not only soft and stretchy, but also very quiet and rustle free. Whilst I've never found that rustling has got in the way of my enjoyment in the outdoors, its absence is actually quite refreshing.

Hood

The predecessor to the Kinetic Alpine, the Kinetic Plus, featured a standard size hood capable of containing a head, but not much more. The Kinetic Alpine hood has been supersized, meaning that it is now helmet compatible. This is clearly great for climbers, but is also a benefit to hillwalkers as it generally feels like a more beefy, weatherproof affair. Fell runners may be a little indifferent though, preferring to save the weight. Still, it's tricky to have a jacket that suits every user's needs perfectly.

When it comes to adjusting this extra volume, it's possible courtesy of two adjusters - one around the rim and the other around the crown - and this way you can get a good fit irrespective of whether you've got a helmet or hat on. Or, if you're anything like me in the picture below, you fail to adjust it altogether (I promise, it's not that difficult).

Other Features

The Kinetic Alpine comes with a small stretchy stuff sack, which is ideal for safe storage. The elastane makes it quite easy to stuff into (not always the case with stuff sacks) and the addition of a reinforced tab means that there's something to attach it to your harness with, without fear that it's going to drop/tear off.

Summary

The Kinetic Alpine promised a lot, and delivered on those promises. Whilst it may not be the most waterproof of waterproofs, it's still pretty waterproof (!!), but it is the breathability that makes it something completely different. With its soft-to-touch feel, a whole lot of stretch, and the fact it comes in at a neat 390g (Rab's figure), this is a superb all-rounder.

Kinetic Alpine Pants

I thought I'd add a separate section specifically dedicated to the Pants. Whilst the various fabric technologies overlap, there are some cracking features and observations on how they perform 'in use' that will no doubt be of interest to anyone thinking of investing in a pair.

In Use

The interesting question about the Kinetic Alpine Pants is whether or not you choose to think of them as an overtrouser, or just a waterproof pair of trousers.

I always think of overtrousers as a kind of necessary evil: you put them on when it gets utterly grim, sweat it out for a bit, then remove them as soon as you possibly can. Clearly the Kinetic Alpine Pants have the benefit not only of being highly breathable, but also very stretchy too, which does make them far more pleasant than your traditional 'overtrouser'; however, if you are looking at using them in this manner it'd be worth sizing them accordingly (again, think slim fit, and maybe go up a size).

What's potentially more appropriate though is to simply wear them as a pair of trousers in their own right, in much the same way as you'd wear a pair of soft-shell pants. I'm unsure as to whether they were specifically designed for this, but my goodness do they work, feeling comfortable and stretchy next to the skin and also making for a nice, lightweight, and windproof layer for those slightly cooler days. The fact you then don't have to worry about having to stop and put them on in the middle of a rain shower is an added benefit.

Other Features

Unlike many waterproof trousers, the Kinetic Alpine Pants come with two reasonably sized pockets which are actually comfortable to put your hands in. There's also a fly, plus a volume adjustment zip on each leg so that you can put them on over a pair of boots. Another nice touch is the rubberised band that runs around the back half of the waist, which helps them stay up.

Summary

Overall, these are brilliant trousers for UK mountain use, and I can see them working well in the Alps too. They beat conventional overtrousers for breathability and comfort, while being far more waterproof than your average softshell legwear. As such they occupy a niche almost to themselves, and offer the best of both worlds in all but torrential rain.