Mammut Whitehorn IN Jacket | Review - Outdoors Magic

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Down and Insulated Jackets

Mammut Whitehorn IN Jacket | Review

Mammut’s new reversible down jacket boasts eco-friendly construction from the inside out – or should that be from the outside in?

Why We Chose the Mammut Whitehorn IN Jacket: Warm, stylish, eco-friendly

Price: £199
Weight: 623g
More info:

The Whitehorn is a cosy jacket to wear. This comes from the fact that the main body is stuffed with 117g of 650 fill power duck down. This is topped off with 200g/m2 of Mammut’s Ajungilak synthetic fill across the shoulders. The zoned construction allies the benefits of natural down as an insulator with the wet-weather resistance, durability and quick-drying properties of synthetic fill. Showing commendable concern for the environment, Mammut have also ensured that both types of insulation inside the Whitehorn jacket are recycled; the down being sourced via Re:down, and the Ajungilak OTI Element being made from recycled polyester.

The face fabric and lining of the jacket are also made from recycled fibres in the form of Pertex Quantum Eco, which has also been treated with a PFC-free durable water repellent (DWR) coating for improved resistance to moisture.

The jacket looks good too, with eye-catching retro styling. Unusually, it is also reversible, and the two different faces offer slightly different looks as well as features. One side has two zipped hand pockets and standard baffles, while the other has a smooth face with two buttoned hand pockets and a zipped chest pocket. Given that wearing either option means you end up with the other set of pockets on the inside, this actually offers a fair amount of storage. The drawback of the reversible design is that it means the main zip has no storm flap, but this is only a minor niggle.

Other features are fairly simple. You get a stand-up, padded collar, elasticated cuffs and a hem drawcord to lock in warmth. There is no hood. The jacket sits nicely on the hips and we’d describe the cut as regular – nicely tailored but not too slim fitting.

In terms of weight, it tips the scales at just over 600g. While this is certainly not heavy, it’s not quite as light as some down jackets. That’s largely because more of that 650FP down is required to offer a decent level of warmth compared to jackets with higher fill powers. It is fairly compressible, but has no dedicated stuff pack or pack pocket.

Still, this is a stylish down hybrid jacket. It is certainly warm enough to see you through a British winter, whether you’re mostly hiking or taking on more extreme sports. It would also be a great piece to take skiing. Wear it one way on the piste, then flip it when you head off the slopes to enjoy some apres-ski.

Tester’s Verdict

Will Renwick, OM Editor

“There’s a lot I like about this jacket, but first and foremost, it’s just how comfortable it is. The loftiness of the down and the large baffle construction make it really, really snug.

“A common talking point within the outdoor industry, is the extent to which recycled down lacks performance quality in comparison to non-recycled down. In my opinion there’s absolutely no evidence of that here. This is super warm. 

“The loftiness of the down and the large baffle construction make it really, really snug”

“The DWR performance for me so far has been good, with the jacket holding up to light rain and drying quickly. It’ll need some topping up with something like Nikwax at some point though, I expect. 

“When the rain really picks up, I’ve found it’s a little bit too chunky to wear underneath a waterproof shell. The torso is fine, but with most of the waterproof jackets I’ve tried, it’s brought about some tightness at the armpits. It’s a standalone insulator really, one to pull on when you’re belaying, or sat on a windy summit. To be honest, it’s the kind of jacket that I could see myself wearing to the pub as well. It’s got that kind of casual style to it – inside and out!

“One small touch that I like is the fact the two handwarmer pockets on the blue side can double as large inner pockets to stash gloves when the jacket is switched around. Come deep winter, when I might need to dry out damp gloves while on the go, that’ll definitely come in handy.”

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Chosen For The Green Gear Guide 2019/20
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