Arc'teryx Proton FL Hoody - Women's Review

If the typical un-lined softshell isn't enough and the thickly-lined versions make you feel heavy and constricted, consider the Proton FL. It promises a lot and, mostly, delivers on all fronts.

Performance Comparison

Plush yet light as a feather, the Proton FL is a great hybrid jacket for a wide range of temperatures and activities.

Weather Protection

The Proton FL is quite decent in this category. It's warm but also easy to layer under something more substantial like a hardshell if needed. It provides a good barrier from the wind and can repel a bit of water, though it's not meant for a deluge. In our shower tests, it got saturated quickly and felt heavy and soggy as a result. It doesn't dry very fast when this happens because of the insulation. If you think your day will involve precipitation, bring along a rain shell as well.

Chilly windy days have nothing on this well-performing hybrid. From belaying at the crag to zipping through town on our bike, the Proton, despite feeling unreasonably light, can keep you feeling cozy and protected. The hood is nicely fitted and only partially insulated so that it will fit neatly under a helmet. While this means it's not as warm, it still provides good wind resistance. The front zip comes all the up under the nose, and the hand-warmer pockets are lined with feel-good fuzziness.

The hood on the Proton FL is only insulated halfway up the back of the head so you won't overheat and it will fit nicely under any kind of helmet.

Breathability

Even though the Proton is insulated, it's still surprisingly air permeable. This makes it a versatile piece, suitable for many different activities and weather patterns. The thin, lightweight design means it's also stellar as a mid-layer worn over a base layer or under a hardshell.

The Proton's Octa Loft insulation paired with the outer Fortius Air 20 fabric allows body heat to escape even when your heart rate is high. The interior feels good against bare flesh with little-to-no clamminess, though the mesh can leave a slight imprint on the skin. The fitted hood is uninsulated from the back of the head forward to help regulate temperature and provide a comfortable fit under any kind of helmet.

Thin yet effective insulation lines the interior of the Proton FL and is covered by a breathable mesh that feels good even next to bare skin.

Mobility

This is a highly easy jacket to move in. It feels incredibly light on the body, and the articulated elbows and gusseted underarms make any activity accessible and non-restrictive. The hood is stretchy and allows unimpeded motion even when under a helmet.

Mobility for the Proton comes with one caveat — it runs a bit small in the arms and hemline. If you have long lanky arms and/or wider hips, you may find sizing up brings you improved comfort and mobility. Style-wise the look will be less fitted through the torso, but if you don't mind the just a bit of bagginess, you'll be happy for the extra room.

Getting some early morning warm-ups laps in the Proton FL. We loved the easy movement and excellent fit of this jacket, but we had to size up to achieve this. The hemline is narrow, so if you have wider hips, consider doing the same.

Weight

We tested all models in our test suite in size medium except for this one. The Proton FL runs small and narrow enough that we decided to size up to a large for better mobility. Despite this, it is still among the lightest jackets in our review.

Even sized up to a large, this jacket only weighs 10.7 ounces. It feels incredibly light on the body and can compress down to a very convenient pack size. If you want a layer that can cover a lot of bases without weighing you down, this is an excellent candidate.

The Proton FL is light on both the body and the scale.

Versatility

The Proton FL is one of the more versatile pieces in our review. It's thoughtfully feature-rich and user-friendly, ideal for rock and alpine climbing, backpacking, hiking, and biking in chilly weather.

The only-partially insulated hood on this jacket means you can use any type of helmet without overheating. Two large chest pockets provide good storage even when wearing a harness, and the hand pockets are softly lined to provide extra comfort and warmth. Both the hood and hemline are quick and easy to adjust to create a tight barrier against the elements, and the insulation is both protective and permeable. The cuffs aren't adjustable but are stretchy enough to fit over thin gloves and low-profile enough to slide under gauntlet-style gloves.

Fuzzy-lined handwarmer pockets and a well-fitted, easy-to-adjust hood make for a great user experience when out adventuring.

Value

As with most things from Arc'teryx, this softshell is not cheap. However, it's well-made, comfortable, warm-yet-breathable, and lightweight. If you want a comprehensive mid-layer that can stand alone or be part of a thoughtful layering system, the Proton FL is worth its hefty price tag. If you just need something simple for occasional use, this is likely overkill, and we'd suggest seeking out a less technical and more affordable model.

This is an expensive layer, but if you're outside adventuring regularly and want something that can cover a lot of bases, it may be worth it.

Conclusion

Often, hybrids don't perform particularly well because they try to do too much at once. The Proton FL is the best we've had the pleasure of testing thus far, hence the Top Pick award. It's warm without being stifling, lightweight, and stretchy while still providing decent weather protection, and the versatile features make it appropriate for many different kinds of activities. The outer material is not as durable as many other models in our review, so you'll want to take some care in that regard, and water-resistance is nominal, so plan accordingly if there's likely to be serious rain. You should also consider sizing up if your arms are long or hips are wide. However, for most all adventures in many different kinds of climates, this is a fabulously useful insulated layer.

Insulated, breathable, and comfortable, the Proton FL is great for a chilly day out hiking, climbing, or biking.