HikingNimsdaiWaterproof Jacket

Nimsdai K2 Winter Waterproof Jacket review: a serious shell that took Storm Austen in its stride

Excellent wind and rain protection, long ventilation zips and a hood built to take a helmet, put through its paces on Dartmoor and the South West Coast Path.

The best test of a waterproof is a bad day, and the Nimsdai K2 Winter Waterproof Jacket got one: a walk on Dartmoor in the aftermath of Storm Austen, with strong winds and spells of torrential rain. It cut the wind, kept the rain out and left the layers underneath dry. We’ve worn it on sustained uphill sections and along the South West Coast Path too, and it’s among the most capable shells we’ve used.

✓  Top PickNimsdai K2 Winter Waterproof Jacket ConstructionGORE-TEX PROWeight481 g (L)RRP£575 The good✓  Excellent wind and rain protection
✓  No visible moisture beneath in our T-shirt check
✓  Long two-way underarm ventilation zips
✓  Helmet-compatible hood with wired peak
✓  Roomy pockets that clear pack straps
✓  Flexible panels at hood and cuffs
The not-so-good✗  £575 is firmly premium

Check out the Nimsdai K2 Winter Waterproof Jacket →

At a glance

Overview

The K2 is a technical, three-layer waterproof shell designed for demanding mountain use. It offers protection from wind and rain while staying practical for year-round outdoor activity, and it pairs GORE-TEX PRO construction with a helmet-compatible hood, a RECCO reflector, extensive pocket storage and long underarm ventilation zips. This is a highly specified shell rather than a lightweight emergency waterproof, aimed at people who need dependable weather protection, freedom of movement and easy access to kit when they’re wearing a pack or a climbing harness.

The brand behind it, Nimsdai, was founded by high-altitude mountaineering and the achievements of Nimsdai Purja MBE. Inside the jacket, the label credits a technical partnership with Montura, and the K2 is made in Moldova.

A note on price

At £575, the K2 sits firmly at the premium end of the technical waterproof market. There are capable shells available for considerably less, so we wouldn’t call this an obvious value purchase. Among highly technical, premium shells, though, it isn’t out of place. Its construction, hood, pocket arrangement, ventilation and climbing-oriented details make it a serious piece of mountain kit, and whether those features justify the price depends on how often you’ll use them.

There’s a brand dimension too. Nimsdai’s identity is bound up with high-altitude mountaineering, and that story will appeal to some buyers, particularly anyone familiar with the 14 Peaks project. Brand association should sit alongside an assessment of performance, though, not replace it. It will be interesting to see how the range develops as Nimsdai establishes itself further in the European market, including whether it introduces products for a wider range of outdoor users and price points.

How we tested

We’ve used the K2 on several Dartmoor hikes, including a day out in the aftermath of Storm Austen in October 2026, when we met strong winds and periods of torrential rain. It proved an excellent barrier against both, cutting the wind effectively and keeping the layers underneath dry. For one of our wet-weather checks we wore it over a grey T-shirt, so any moisture getting through would be easy to see. After roughly 30 minutes of walking in the rain we took the jacket off and found no visible wet patches on the T-shirt. We also had no noticeable water ingress or seam problems during these outings.

Further Dartmoor walks included sustained uphill sections, which let us judge breathability and temperature regulation while working harder. The long underarm zips proved useful for managing airflow, and we didn’t notice any clamminess or overheating in the cool, windy conditions. The jacket also worked well as a windproof outer layer over lighter clothing. As with any waterproof, the layers underneath and your level of effort will affect comfort, but the ventilation options make it easier to manage changing effort.

We wore the K2 on sections of the South West Coast Path as well, with repeated climbs and descents and plenty of changes in pace. Those walks tested comfort over longer periods, freedom of movement, pocket access and how the jacket sat with a backpack. The chest pockets stayed accessible around the pack straps, the sleeves let us reach and move without riding up, and the jacket stayed comfortable over a full walking day. All of this was autumn testing in British conditions.

Features and performance

Weather protection

The K2 uses a three-layer GORE-TEX PRO shell. Nimsdai’s product information gives a waterproof rating of 28,000mm and a RET breathability figure below 6, but those are manufacturer specifications rather than measurements we took. What we can tell you is how it behaved: strong protection from driving rain and wind in everything we’ve met so far, with no seam problems and no water getting through.

“After roughly 30 minutes of walking in the rain, we found no visible wet patches on the T-shirt underneath.”

Hood, helmet compatibility and RECCO

The hood is large enough to work with a climbing helmet and also sits comfortably over a cap. A wired peak helps keep your face clear, and the adjustment system lets you bring the hood in closer around your head. It’s easy to adjust with gloves on, and the rear adjustment has a generous loop. A RECCO reflector is built into the hood.

What we noticed most is the flexible construction around the hood. It lets the hood move naturally and reduces the rustling noise that can otherwise be distracting around the ears, which helps you stay aware of what’s going on around you.

Flexible panels at the cuffs

A flexible, honeycomb-like material is used around the hood and cuffs to improve articulation. At the cuffs it makes the jacket easy to work around winter gloves, and we can move the sleeve to check a watch without undoing the hook-and-loop adjustment. Nimsdai’s product video also highlights the cuff construction as helping to limit snow and debris travelling up the sleeve during climbing, though we haven’t tested that.

Ventilation, zips and pockets

The underarm zips are exceptionally long, running from around the upper arm towards the hip. They open wide and can be adjusted from either end, so you can change the size and position of the opening to suit how hard you’re working. On the uphill sections that gave us useful control over airflow.

The main front zip is a two-way YKK VISLON, which is handy when you’re sitting, moving around a harness or reaching kit underneath. It runs smoothly and has a substantial webbing pull. It takes a deliberate action to operate, but we haven’t had any snagging or stiffness, and the lower slider hasn’t worked its way open in use. An integrated waist tensioner can be drawn in to help stop wind, snow or debris getting in from below.

The pocket layout is generous. Two big chest pockets sit clear of backpack straps, and there are two lower hand pockets, a ski-pass pocket on the left sleeve and three internal pockets: two mesh pockets (one with a hook-and-loop closure) and a separate zipped security pocket. Each external pocket is large enough for a winter glove, and the chest pockets stay accessible while wearing a rucksack. The external zips are storm-sealed with toggles, and the orange cord pulls and branded toggles are easy to use with gloves on.

Fit, weight and packing

The K2 has a fitted cut. We assessed it with a winter layering system in mind, and the size we wore leaves room for those layers. For everyday wet-weather walking over a single midlayer, a closer fit may suit you better, so check Nimsdai’s size guide before you choose.

At 481g in size Large it’s a substantial technical shell, but it’s impressively light given its feature set and intended use. It isn’t an ultralight emergency layer, and the weight is reasonable for a fully featured GORE-TEX PRO jacket. It also packs down relatively small for a technical shell. We tend to roll it loosely into its hood, which is simply our own way of stowing it rather than a packaway feature designed by the manufacturer.

Inside the jacket

Inside, the label reads “Nimsdai – Defined by the Elements. Engineered by Montura”, a brief indication of the technical partnership behind the garment. Above the right chest pocket is an embossed message from Nimsdai Purja MBE: “Everything in life is possible. Armed only with a determined approach and a positive mindset.” It’s a personal detail that will resonate with people familiar with the 14 Peaks story, although it doesn’t affect how the jacket performs. Nimsdai Store also states that 5% of its profits are donated to the Nimsdai Foundation.

Small details and what we haven’t tested

The K2 isn’t perfect, though the faults are small. The lower slider on the two-way main zip is the only zip pull without a toggle, which is a minor inconsistency rather than a functional problem. We’d also treat the flexible material around the hood and cuffs with a little care, avoiding repeatedly pulling the hood adjustment tight around the membrane-backed fabric. That isn’t a fault, just a sensible way to look after a technical garment, and neither point has caused us a problem in use.

The bigger caveat is scope. Our testing covers autumn weather on Dartmoor and the South West Coast Path. We haven’t yet assessed the K2 in prolonged sub-zero conditions, heavy snowfall or high-altitude environments, so please read this as an autumn UK review rather than a full winter or alpine verdict.

How it compares

The K2 sits in a premium corner of the market, and the comparisons aren’t entirely like-for-like. At around £370, the Patagonia Triolet is a lower-priced technical shell, while the Helly Hansen Odin 9 Worlds 3.0, at around £470, is a premium mountain shell with a similarly technical focus. The Mountain Equipment Lhotse is another high-specification waterproof aimed at serious mountain use, at around £520–£550 depending on the stated RRP and retailer, and The North Face Summit Mountain GORE-TEX Pro is the dearest of the group at around £740. Those are indicative UK prices that shift with retailer and season, and we haven’t tested these shells against the K2. Against that field the K2 is expensive without being out of place. Of the shells we’ve used it’s among the most capable, and it’s the one we’d choose for bad-weather walking, for the way it kept out Storm Austen’s wind and rain, stayed comfortable on long days and gave us real control over ventilation.

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Our verdictA premium, highly capable shell that delivered in the wet and wind we met this autumn.If you need a serious waterproof layer, the K2 Winter Waterproof Jacket is a credible option. It gave us excellent protection from wind and driving rain on Dartmoor, a dry T-shirt after half an hour in the rain, comfortable all-day wear on the South West Coast Path and useful ventilation on the climbs. The hood, the pocket layout and the long underarm zips all earn their place, and the specification and mountain-focused design feel considered throughout.It won’t suit everyone. At £575 it’s beyond many buyers’ budgets and not an obvious value purchase, the lower zip slider lacks the toggle the other pulls have, and we’ve only tested it in autumn UK conditions, not in sustained sub-zero weather, heavy snow or at altitude. Within those limits, it’s among the most capable waterproofs we’ve used, and it could well become our benchmark for bad-weather walking.Check out the Nimsdai K2 Winter Waterproof Jacket →

FAQs

How waterproof is the Nimsdai K2 in heavy rain?Very. In the aftermath of Storm Austen it kept out strong winds and torrential rain, and after around 30 minutes of walking in the rain a grey T-shirt underneath showed no visible wet patches. It’s a three-layer GORE-TEX PRO shell, and Nimsdai quotes a 28,000mm rating that we haven’t tested ourselves.

How breathable is the K2 on uphill walks?We didn’t notice any clamminess or overheating on sustained uphill sections in cool, windy autumn conditions, helped by the long two-way underarm zips. Nimsdai quotes a RET figure below 6, which we haven’t measured.

Does the K2 hood work with a helmet?Yes. The hood is large enough to work with a climbing helmet, and it also sits comfortably over a cap. A wired peak helps keep your face clear, and a RECCO reflector is built in.

How well does the K2 pack down?It packs down relatively small for a technical shell. At 481g in size Large it isn’t an ultralight emergency layer, and we tend to roll it loosely into its hood to stow it, which is our own habit rather than a designed packaway feature.

Is the Nimsdai K2 worth the money?That depends on how often you’ll use its features. At £575 it’s firmly premium and not an obvious value purchase, but the specification and mountain-focused design are serious, and we think it’s a credible choice if you need a serious waterproof layer.