Hispar Down Jacket: K Series

'K Series' version of our lightweight high-altitude mountaineering jacket. Warmth to weight at the limit of possibilities via design innovation and unique materials. Now also available in custom sizes.
Typical Operating Temperature
Guideline minimum temperature. Sleeping Bag TOT: you should get a night’s sleep, under normal circumstances. Clothing TOT: you should feel warm enough, assuming low/moderate activity. Sleep System TOT: relates to full system. For more details, see our Technical Briefing.
-30°C / -22°F
For clothing, weight is for size: M. For sleeping bags, weight changes with selected length/width. N.B. there may be some variation in the weights of finished products.
575g / 20oz
Hispar Down Jacket K Series (Orange & Charcoal)

Phenomenal. I've never before come across one anything like this warm at this low a weight.
Chris Townsend in TGO Magazine.



  • A PHD K Series product: Ultimate warmth / weight ratio
  • PHD's Unique 1000 fillpower down
  • Water-resistant Ultrashell outer fabric. An excellent balance of weight, water-resistance and breathability
  • Superlight 10X inner fabric. Down-proof, wind proof and super soft
  • Box-wall construction for maximum loft
  • Front closure:
    • 2 way zip
    • Outer zip baffle with intermittent Velcro + 3/4 length internal baffle
  • Pockets:
    • 2 chest pockets above harness level
    • 1 inside
  • Hood:
    • Box walled
    • Elastic face cord
    • Volume reducer
    • Zip on
    • Hemet-sized
  • Elasticated hem with double-exit shock cord
  • Adjustable Velcro cuff closure
  • Elasticated inner back for fit
  • Fleece lined collar
  • Stuff sac
  • Pack size: 20 x 34cm*

*Please note: We make our stuff sacs big enough to allow fairly easy stuffing rather than reducing the jacket to the tightest minimum.


This K Series product has been created for one single reason, to take warmth-for-weight performance to the limit of what's possible. Unique 1000 down, super-light materials, and specific design features mean that the word Ultralight now applies to this wide range of gear that will take you to the Poles as well as on a Sahara Marathon. More on the K Series...

Also available in custom sizes. We make clothing to order, so if you’re not a standard size we can make it to fit. To order a non-standard custom size, select the Custom Sizing tab, choose your body width, and then the body/arm lengths, shorter or longer, that work for you. A custom size takes us a little longer (typically two weeks longer) to make and, because it’s personalized, it’s non-returnable and our customer loyalty scheme can’t be applied.

Highly Commended TGO Magazine Gear of the Year AwardsThe Hispar jacket was originally designed to be the lightest down jacket you would think of taking up a 7000m peak. The K Series Hispar goes a step further. With the use of specialist new fabrics Ultrashell and 10X along with PHD's 1000 down we've made the lightest even lighter. This is still a fully capable high mountain jacket rated at -30°C with box walls, chest pockets, an internal water-bottle pocket, and a large helmet hood: but it weighs in at just 575gm. Wear it or pack it, you'll feel the benefit from the lightest piece of high-altitude kit available.




Ultrashell (weight: 40 gsm)

One of the lightest of PHD's coated materials. This ripstop nylon provides complete wind block and good water resistance at minimal weight. Ultrashell gives an excellent upgrade to performance with very little weight penalty.

Ultralight 10X fabric (weight: 26 gsm)

10X, PHD's first 10 Denier Fabric. 9,000 metres of the yarn used to weave 10X weighs just 10g, that's about the same as a £1 coin! For all its thinness 10X is amazingly downproof and with reasonable care will go on giving you good service for years.

1000 fillpower down

This rarest of all downs we reserve for the K Series. European goose down of unique quality. 1000 provides the highest warmth-for-weight performance possible from down. More on our down insulation.

"Highly Commended" TGO Magazine 'Gear of the Year' Awards

Highly Commended TGO Magazine Gear of the Year Awards

"This is a phenomenal jacket. I've never before come across one anything like this warm at this low a weight. I've also never come across 1000 fillpower down before. The design is excellent. The Velcro-closed hood is amazingly warm and the insulated pockets lie above a pack hipbelt. The Hispar K is longer than most insulated jackets too and has a waist drawcord as well as a hem one. If you want an incredibly warm jacket at the lowest possible weight this is the one."
Chris Townsend, Gear Editor, TGO Magazine. Read full review.

"The loft is just absolutely INSANE! Unbelievably lightweight! And unbelievably warm for the weight! It is the best down jacket I have ever seen and tried on."
Petar J Skundric

"My K-Series Hispar down jacket kept me toasty warm to the summit of Island Peak. Such a luxury having something that fitted so well, kept me warm, and was so light I hardly noticed I was wearing it! Cheers!"
Philip Tonkin

"The Hispar K Jacket is superb.  I bought it specifically for Arctic Ultra races and it has been perfect.  The cut and functionality is excellent.  It fits like a glove and has the ease of movement of a light down jacket but the warmth and protection is incredible. It is a pleasure to use. I highly recommend it."
Ben Clayton-Jolly

The comments below are for the standard Hispar Jacket, which is 150g heavier:

"For warmth the Hispar Jacket is the lightest I've used."
Tom Richardson in Climb Magazine.

"The Hispar is a totally amazing jacket. Really surprised by the warmth it offers. Amazing warmth to weight. Used it on 3 Aconcagua expeditions this season and it was just ideal."
Ben Kane, Guide, Field Touring Alpine.

"It came up the Moonflower with me and I bivied in about -20 degrees C in just the Hispar down jacket and a superlightweight bothy bag and that was fine. The kit is incredibly efficient weight vs warmth. The down that you use is just insane for lofting power."
Jonathan Griffith using the Hispar Jacket on the Moonflower Buttress in Alaska, USA.

"The Hispar Jacket and Hispar Sleeping 400 Bag arrived in California yesterday. I'm over the moon to say the least. The build quality is excellent. Consider me a totally satisfied customer, please pass my thanks on to the team."
Rory Abbott.

"The Hispar jacket has kept me warm in minus 30 C with a warm sweater and thick wool underwear, even when standing still for hours icefishing. So I am very happy with it."
Jeanette Lykkegard Nielsen using the Hispar Jacket studying reindeer headers on the Kamchatka peninsula, Siberia.

"The Hispar more than lived up to the sky high expectations and has delivered time and again. I've only worn it in minus 15C so far but even with just a base layer underneath I needed to have the zip halfway down to avoid meltdown! It is a wonderful piece of kit and is worth every penny."
Marcus P.

"My new Hispar jacket arrived this morning ... it's brilliant thanks and I'm delighted with it."
Rowan Huntley.

"Great down jacket from the English expert for down clothing, PHD."

"Many thanks for rushing the Hispar down jacket through. I certainly needed it. The weather on Ama Dablam was settled but cold and I would have been stuffed if it wasn't for the jacket."
Tim Ralph.

"Thank you for the fantastic equipment. Everything (including the Hispar Down Jacket) was above and beyond what was required and fended off the elements perfectly."
Graham B., on a trip to Aconcagua.

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