A very light softshell layer (SL=Superlight) designed primarily for walkers, the Gamma SL Hoody is handy to have about you when you don't know what the weather will bring. It gives minimalist insulation for warmer conditions, whilst also working as a windproof/weather resistant outer on top of other layers in cooler weather. Being quite breathable, and stretchy, I've found it a good top for wearing on the go in variable conditions.

What's it for?

According to Arc'teryx, this jacket is designed for hiking, and a 'range of active mountain adventures'. Think hillwalking, backpacking, general outdoor use and travel. It is light and thin enough to be stuffed in a bag, ready for when you need it, and has the added value of being something you would be happy to wear in daily life (no dayglo orange in this colour range - the only downside being that on a dreich day there is a danger you could blend into the landscape).

If you want something with more climbing-oriented features such as a helmet-compatible hood, then the heavier Arc'teryx Gamma LT Hoody might be more what you need.

Weight

My women's size L jacket weighs just 279g (Arc'teryx say 238g, which must be a smaller size). This is respectably light for a softshell of this nature, putting the Gamma SL Hoody into roughly the same weight bracket as alternatives such as the Mountain Equipment Squall or the Rab Borealis (though it's less of a climbing top than either of those). An out-and-out wind shell would weigh considerably less still, but I think for most hillwalkers a sub-300g softshell is generally going to feel light enough, and in cooler conditions or when scrambling it offers more protection than something skimpy and ultralight.

Fit

With quite a roomy body, this softshell can fit easily over several other layers - for instance on colder autumn days I've worn it over a baselayer and a light insulated jacket, without it all getting too bulky or restricting. Amazingly it still manages to provide a slightly fitted feel, which is both practical and reasonably flattering: It's not so baggy that it looks or feels like a sack when put on over just a T-shirt.

There's a Gamma SL Hoody for both men and women, each coming in a decent range of sizes. My women's size Large equates to something like a 14. Arc'teryx jackets often seem to come out on the short side, but here there's sufficient length in the hem to keep the breeze out at the waist.

Thanks to the active cut of the sleeves, arm movement is unrestricted and hem lift is minimal when I raise my arms. There's also enough room for my broad shoulders.

Fabric

You get no insulation or backing material in this jacket, just a single layer of fabric. They have used something called Fortius 1.0, a double weave Nylon/Elastane blend that has a little bit of stretch to give you more freedom of movement. It's light and thin, but feels strong for its weight, and I think it should stand up to a fair bit of abuse - scrambling, for instance or dodging gorse-edged bogs, whichever takes your fancy.

Being both highly wind-resistant and surprisingly breathable, this fabric seems ideal for a light softshell designed for active use in the mountains. I've never felt sweaty walking uphill, and it wouldn't be out of the question to wear the Gamma SL when running in cooler weather.

It's not fully waterproof, by any means, but water beads impressively well on the face of the fabric, so you can wear the Gamma SL Hoody in light on-off showers without stopping to put on and remove a shell every few minutes. After several months of use this surface repellency has yet to wear off. The fabric is quick drying, too.

Features

There aren't many add-ons here, and that's really the point of this minimalist softshell.

The two zipped hand pockets are a decent size if you want to carry thin gloves or a hat, and they're mesh lined so that they double as fairly effective vents. For use with a harness, the pockets are positioned a bit too low (but then this isn't officially a climber's jacket). The other obvious downside is that there is no reversible stow pocket. This sort of light softshell is ideally suited to stuffing into its own pocket for neater packing, or for hanging off a harness. While a stow pocket is something that you'd be more likely to miss on a more climbing-oriented model, I think it'd have been nice to see one here too.

At the hem there's no drawcord, but just some light elastication. Oddly, the men's version does have a hem drawcord, and adding one to the women's jacket too would have made this softshell a little more storm-worthy since the wind would be less likely to get up and under. Similarly, at the wrist you don't get the usual hook-and-loop adjustment tab, but just a bit of elastic. The cuffs can easily be pulled over a glove, but that's because they're very loose-fitting anyway and the stretch is basically unnecessary. If you wanted to tighten up the fit at the wrist to keep out the weather, you'd be out of luck. The hem and cuffs suit a softshell designed for lighter use in less hostile weather, but year-round hillwalkers might occasionally find themselves wanting a more cinched-in, wind-resisting fit.

The so-called 'StormHood' is, again, at the lighter duty end of things. You get a laminated brim with just enough structure to resist flapping in moderate wind. If things got genuinely stormy you might want a sturdier hood, but in the sort of less demanding use that the Gamma SL is designed for it does the job well. The fit can be pulled in close using the single rear adjustment toggle, and unlike some hoods you get decent peripheral vision (a mixed blessing in a side wind!). However it won't fit properly over a helmet - for that you'll want the more climbing-friendly Gamma LT.

Summary

Its nice active cut, minimalist design and light-but-tough fabric make the Gamma SL Hoody a bit of a winner if you're after a lightweight and versatile softshell for walking and general outdoor use in less challenging conditions. The £140 price tag seems quite top-end for something this simple, but it does feel high quality and made to last.

Arc'teryx say:

The Gamma SL Hoody is the result of years of Arc'teryx softshell experience and our designers' extraordinary focus on purity of function. It is a pinnacle piece combining advanced performance and a clean, minimalist aesthetic. The Fortius™ 1.0 double weave is light, but strong. It resists wind and water, breathes, and offers four-way stretch. A StormHood™ provides protection without impacting peripheral vision, while the trim fit, articulated patterning and clean lines keep it streamlined and comfortable.

• Sizes: XS-XL (women) XS-XXL (men)
• Weight: 238g (Arc'teryx's weight)
• Fabric: Fortius™ DW 1.0 - 87% Nylon, 13% Elastane
• Breathable, wind resistant, water resistant
• Mechanical stretch textile
• Trim, slim fit, optimizes exceptional breathability during high output
• Articulated patterning for unrestricted mobility
• Gusseted underarms provide a stationary hem that does not lift with overhead motion
• Adjustable low profile StormHood™
• Low profile elasticized cuffs
• Elasticized bottom hem
• Two hand pockets with zippers

For more info see arcteryx.com