Extensively tested and reviewed by Cairngorm Treks in autumn and winter conditions 2018/19 in the Cairngorms and surrounding mountainous areas.

The Montane Hydrogen Extreme Smock, as the name suggests, has pretty big boots to fill. For over 20 years the original Extreme Smock has been regarded as a very dependable layer for expeditions into some of the world’s most hostile environments. Montane state that this updated version is inspired by the tried and tested Pile/Pertex system technology of the renowned Extreme Smock. The new Hydrogen Extreme utilises the same 2-layer softshell concept in a modernised, lighter and even more breathable package.

Coming in at nearly half the weight of the original smock at 506grams, in size medium, and with a change of insulation to a Polartec Alpha Direct Insulation 120g/sqm, this is certainly a lighter and more packable version than the original Extreme Smock. We already know from previous experience that Polartec Alpha Direct insulation is extremely breathable, working with the body to regulate temperature and keep you comfortable. This is by far the highest weight for this type of insulation we have used, and with high expectations we are looking forward to how the Hydrogen extreme performs throughout a Scottish winter.

Straight away we can see many similarities and differences between the Extreme Smock and the Hydrogen. The main obvious difference is the hood is now built into the smock instead of being removable. With the lighter weight and bulk of the Polartec Alpha we believe Montane didn't need to include a removable hood as the Hydrogen Smock will fit under additional layers without feeling restrictive. Another noticeable difference is the outer fabric. Pertex Quantum Air nylon outer with DWR Pertex Quantum Pro water-resistant rip-stop nylon forearms makes for a lighter and more breathable option. This is another fabric we have experience of using and is becoming a popular pairing with Polartec Alpha as the they work together to provide excellent breathability whilst also acting as a layer of protection against light showers and snow fall.

Montane have been wise to keep some of the great features of the Extreme Smock and apply these to the Hydrogen. A large front dropped pocket, free from interference from rucksack straps and climbing harnesses is one of the main reasons people opt for a smock style jacket. We have been big fans of this design, and the ability to quickly store a large amount of items within this pocket is a great option, especially when considering winter navigation and general photography.

The colour we received is the Narwhal Blue, it's subtle and pleasing to the eye paired with red zippers. As a layer to be worn mostly in winter we would like to see Montane give some high visibility options as the only other colour available is a dark grey.

Two zippers either side of the dropped pocket also open up fleece lined hand warmers which can also be utilised as an extra-large pocket. Positioned just behind these there are a couple more two-way zipped side vents that offer great ventilation but also aid with the wearing and removal of the Smock. This is a tight-fitting garment, which is meant to be worn on top of a base layer or next to the skin. This better wicks away perspiration, and as with our previous experience, the combination of Polartec Alpha and Pertex Quantum Air mean even when working hard on a difficult ascent we have found the combination to be one of the best for mitigating any build-up of moisture. In a size medium it we found the length of the torso to be a bit on the short side and would recommend anyone taller than 5’ 9” to consider opting for a larger size.

As the insulation works with the body this is not a layer in which standing around will keep generating warmth. Although first impressions would imply that with an increased insulation fill of 120g/sqm it might be a bit warm, used as a single layer on top of a long sleeve base layer was perfect for most winter activities and never felt heavy or restrictive. Although additional layers will be needed when stopping for breaks or at camp. Likewise, if increased wind speeds begin to chill or heavy spells of precipitation persist we found that extra layers were needed. Being a relatively low-bulk jacket, the Hydrogen Smock will easily fit under another layer without feeling too restricting.

So, let's move on to the star of the show. Something which cannot be underestimated especially in winter and that is the hood. A fully adjustable hood with three-point adjustment and stiffened peak. It’s lined tactfully with the same 120g/sqm Polartec Alpha. Once worn, it offers the same comfort, warmth, and breathability as below, and takes the Hydrogen Smock to a whole new level. We have used a wide range of down and other synthetic jackets and we have to say this is one of the best hoods we have ever used. As the Polartec Alpha follows continuously through the jacket to the hood there are no cold spots. This is especially great around the ears, and when combined with a balaclava and goggles gives complete protection from the cold.

The Pertex Quantum Air with its DWR finish is fantastic at keeping light showers and snowfall from soaking in and forming into ice and impacting the insulating properties of the smock. The DWR Pertex Quantum Pro water-resistant rip-stop nylon forearms further mitigate any light precipitation from forming damp spots which is great to combat against moisture build up on creases. We found that even when moisture does start to dampen into the smock if you're working hard your body heat will push out that moisture. As this isn't a fully waterproof shell it has to be noted that an additional hard shell layer will be needed in heavy snowfall, sleet, and rain.

Our Verdict

It's hard to fault the Montane Hydrogen Smock as it is a well thought out product which is perfect for high paced Scottish winter activities. We all love those amazing cold and dry winter days when all clothing and gear works perfectly. Unfortunately, in the UK, days like these are few and far between. Temperatures can often fluctuate throughout a day, so damp cold conditions need consideration with clothing for anyone seeking a winter adventure. A retention of moisture within our clothing will lead to a reduction in efficiency. Montane have created a smock that we have found to be one of the best on the market in mitigating this problem. Using a beefed up120g/sqm Polartec Alpha Direct Insulation combined with a Pertex Quantum Air nylon outer stops any build-up of moisture, whether it's from perspiration, light snowfall, or showers. The choice of insulation works with the wearer to maintain a comfortable level of warmth, this is then aimed at high activity mountain walking or climbing so remember you will need to take extra layers to keep warm when stopping for breaks or around camp. If you were a fan of the original Extreme Smock you will really get on well with the Hydrogen.

Cairngorm Treks is a small family business based in the picturesque village of Tomintoul in the North East region of the Cairngorms National Park. They provide bespoke Mountain Guiding for Single Day Walks and Lightweight Multiday Trekking experiences, including wild camping, in the stunning Cairngorms wilderness and surrounding areas. Whether in the high mountains or lower valleys, their Multiday Treks are equipped with high quality, lightweight camping and trekking gear. They only work with small groups and, whatever your ability, pride themselves on designing your outdoor experience completely to your needs and with professional guidance and expertise. Adventure is waiting...