Rab Phantom Waterproof Jacket review: an impossibly light and packable layer, ready for every trail run

Rab Phantom Waterproof Jacket: first impressions 

The best type of running jacket for trail runners is one that's so light and packable you never think twice about stuffing it into your hydration vest, and this jacket excels with its barely-there design.

Made using a 7D Pertex Shield 2.5-Layer construction, it's almost impossibly light and packs down into its own hood, so you can stash it in just about any pocket. The fabric is treated with a PFC-free DWR, and the jacket does a great job of repelling light rain and is very windproof. It won't hold up against torrential rain, however.

Rab has stripped away all the extras, such as pockets and toggles, and the only thing adding any weight at all is the full-length zip, which comes all the way up past your chin to provide extra protection from the elements and secure the hood. The hood is elasticated and has a toggle at the back so you can cinch it tight when the wind picks up.

The cuffs and hem are also elasticated to help find a snug fit, and the cut is slim enough to be functional while allowing for excellent freedom of movement.

Despite its light weight, it doesn't appear to be a particularly fragile jacket and has held up to months of testing without showing any signs of wear, never mind tear.

Is it pricey? For the occasional wet-weather runner, yes absolutely. But compared to jackets we've tested previously, it's somewhere in the middle, despite being one of the best, and if you go out in all conditions, then it's worth it.

Rab Phantom Waterproof Jacket: in the field 

I've spent the latter half of spring and the entire summer testing out Rab's newest trail running gear, on runs ranging from the Highlands of Scotland to the Lake District and Yorkshire Dales National Park in England.

In addition to the Rab Talus 2-in-1 shorts, which I absolutely adore, and the Rab Veil 12L Lightweight Running Pack, I've worn this jacket a fair bit, and packed it away in my vest even when the forecast doesn't call for rain. Though Scotland has had an actual summer for once, I've still had plenty of occasion to test it out against mist, drizzle, and torrential rain.

Here's how it performed:

Sizing and fit

I tested the XS, which is a UK 8, and I'm glad I didn't try the small as I think that would be too big and flappy. It might just run the tiniest bit big, but on me this size leaves enough room for layers, which will be useful when winter arrives, and isn't too loose, thanks in part to partially elasticated cuffs and hem.

Weight and packability

The first thing that stood out was how unbelievably light this jacket is. It's exactly half the weight of my North Face Lightriser Futurelight running jacket and, unlike a lot of garments that claim to pack away inside their own pockets, this one really does fit into a pocket on the back of the hood.

I don't even notice it when I'm running, and it will basically always be in my hydration pack moving forward, no matter the weather or the season.

Weather protection and breathability

This jacket has a 2.5-layer construction, and it's made for running, so I didn't expect it to hold up against heavy rain, but regardless, I found myself wearing it in a downpour during my first outing in it back in the spring. I was running in rain and wind (but fortunately not severe cold) for about 90 minutes, and when I got back to my car, I was quite wet down my front around the zip and on my shoulders.

I wouldn't expect any running jacket to really repel that type of weather, and I wouldn't use this as a replacement for a proper 3-layer waterproof for hiking, but it really is excellent in light rain and holds up for quite a long time.

Despite that decent level of protection, this jacket is surprisingly breathable, and I'm amazed at how often I've simply kept it on for an entire run when the rain has stopped (or hasn't started) because it's perfectly comfortable.

You might think that would translate into a smelly jacket, but I've just given the pits a sniff and there's absolutely no odor at all, after months of use, which is another thing I can't say for my other running jacket.

Storage and hood

There are no pockets, but since I wear a vest (and the Rab Talus shorts) I really don't need them and personally wouldn't want something bouncing around in my running jacket pocket anyway.

The hood is just great, staying put thanks to a toggle at the back to tighten it and the high collar, which helps protect my face when it's blowing sideways.

For all its wear, it still looks absolutely brand new and I'm planning to wear this jacket for many years ahead.

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