Kathmandu Seeker PrimaLoft Active Vest review: a lightweight gilet that adds warmth without bulk for cold weather layering

Kathmandu Seeker PrimaLoft Active Vest: first impressions 

Hiking vests – or gilets as some call them – have a bit of a reputation for being cozy, bulky layers that keep your vitals warm but deliver more breathability than a fleece jacket. This one provides those benefits, but without all the bulk.

Tipping the scales at just eight ounces, this super light and sleek-fitting vest delivers surprising warmth thanks to the PrimaLoft insulation, and with a durable, water-repellant shell it's an effective outer layer in cool weather when worn over a base layer. When things turn really cold, the low profile design makes it easy to throw another layer or two on top without feeling like the Stay Puft Marshmallow Man on the hill.

The high collar keeps out a cold breeze and the adjustable hem helps to cinch things tight. Two zipped hand warming pockets keep your fingers or warm or hold small pieces of gear, while a chest pocket means you can easily access your phone for directions or photos even when you're wearing your backpack.

The vest is treated with DWR so you don't have to go for your waterproof just because there's a few minutes of light drizzle, and added four-way stretch makes sure you're comfortable no matter what.

If you wear this for high-intensity adventures in milder weather, it will get a bit stinky like any synthetic top, but other than a higher price tag, we can't find much else to complain about.

Kathmandu Seeker PrimaLoft Active Vest: in the field 

It's taken me a few years to really get down with vests, or gilets, but they've become a staple for me in the fall when it's chilly, but I don't yet need to properly layer for winter. I have a thick fleecy gilet which is super cozy for autumn walks but a bit bulky for layering, so I was curious to try one that was obviously much lighter – could such a non-cozy vest really deliver the warmth I want?

I've been hiking in this for the past couple of months as the weather has turned from mild to cool to cold and wet to find out.

Here’s how it performed:

Sizing, fit and comfort

I tested a small, which is my usual size, and I'd say the fit is pretty perfect. It might be slightly looser on me than the model, but I'm on the small end of small and it means I can easily wear it over a thicker base layer. The fit is slim and active and the addition of four-way stretch means it should work for lots of different shapes and sizes and adds comfort.

The shell material is really soft so I can zip it all the way up to my chin with no rubbing or chafing.

Insulation and breathability 

Clearly, the whole point of a gilet is to retain and and even though this doesn't look like it would be as warm as a puffy or fleece vest, I feel instantly warmer the moment I put it on and that's obviously thanks to the PrimaLoft insulation.

Because it doesn't have sleeves, any vest really should be breathable and I can't say I've had any issues with overheating or feeling clammy in this. There was one hike where I wore it on a mild but damp day with a hardshell on top. My outer layer definitely wasn't breathable and so a fair bit of condensation built up inside my jacket and this gilet ended up a little damp. It took a little longer than I'd have expected to dry out, given the materials it's made from, but mostly I think this was down to poor layering.

Weight and packability

Where this vest really shines against some others is how light it is for the warmth it provides. It's thinner than my lightest softshell jacket but keeps me every bit as toasty as a bulkier version (and, for that matter, a lot of my jackets). Basically, I don't even notice I am wearing it except for the fact I'm warm and comfortable.

Obviously this means I can wear it with with a down jacket and a waterproof jacket on top if I need to, but it also makes it tremendously packable. It rolls up even smaller than my water bottle, so it's an excellent extra layer for a day hike, and makes a really good choice for travel, too.

Storage and durability

Every vest needs handwarming pockets, in my opinion, because I usually wear them when it's cool but not cold enough to need gloves. However, I was super pleased to see if also has a chest pocket because I can whip my phone out to check AllTrails or take photos even when I'm wearing my backpack.

Compared to synthetic puffer gilets, this one is definitely more hard-wearing. The ripstop nylon shell isn't showing any signs of rubbing from my backpack straps.

Value

This is a pricier vest than most of the ones we've tested, though for that you're getting a high-performing gilet that's arguably more versatile than most, because of how light it is. I think if you love a gilet and are looking for one that's really built for active adventures that you could wear all year round, you'd be pleased with your purchase.

Kathmandu Seeker PrimaLoft Active Vest: the bottom line 

This lightweight vests packs down small but is a powerful performer when it comes to adding insulation. Its streamlined design means you can wear it in most seasons, whether as a light outer layer for cool summer nights or if you want to add another layer for frigid adventures but still want to be able to bend your elbows.

It's pricey, but effective. If you're looking for something with a leaner price tag but similar specs, check out the Helly Hansen Paramount Softshell Vest in comparison.

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