Alpine Ultra Down Jacket: K Series

'K Series' version of our lightest climbers' down jacket with chest pockets and optional helmet-sized hood. Lighter and warmer than fleece. Warmth to weight at the limit of possibilities. Now also available in custom sizes.

Typical Operating Temperature

-10°C / 14°F

Weight

295g / 10oz

Price

$773.84

Packs to nothing.
Petesy (a.k.a. Peter Macfarlane).

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Size

What’s my size?

Sizing

Standard Sizing

The PHD Sizing Chart below is based on measurements without clothing, exactly the way you would buy a shirt or a sweater. A 42" (107cm) chest means that your bare chest uninflated measures 42". Inside Arm is measured from armpit to wrist-bone.

Size	Height	Chest	Waist	Inside arm
XS	155-163cm (5'1"–5'4")	86cm (34")	71cm (28")	46cm (18")
S	164-170cm (5'5"–5'7")	91cm (36")	76cm (30")	48cm (19")
M	171-178cm (5'7"–5'10")	99cm (39")	84cm (33")	51cm (20")
L	179-186cm (5'10"–6'1")	107cm (42")	91cm (36")	53cm (21")
XL	187-193cm (6'2"–6'4")	114cm (45")	99cm (39")	56cm (22")

Custom Sizing

Once you've selected a Body Width you can choose Body Length and Arm Length up to two sizes bigger or smaller. For example, a jacket with a medium (M) Body Width can be XS, S, M, L, or XL in Body Length and XS, S, M, L, or XL in Arm Length. If you have any questions about your size, please contact us.

Body Width. Use the chart below to find your Body Width. Measure yourself without clothes, relaxed with an uninflated chest.

Body Width	Chest circumference	Waist circumference
XS	86cm (34")	71cm (28")
S	91cm (36")	76cm (30")
M	99cm (39")	84cm (33")
L	107cm (42")	91cm (36")
XL	114cm (45")	99cm (39")

Body Length -- can be two sizes up or down from Body Width. Use the chart below to find your Body Length size. Measure your height without shoes:

Body Length Size	Your height in cm	Your height in inches
XXXS	139 - 144cm	4'5" - 4'8"
XXS	145 - 154cm	4'9" - 5'
XS	155 - 163cm	5'1" - 5'4"
S	164 - 170cm	5'5" - 5'7"
M	171 - 178cm	5'7" - 5'10"
L	179 - 186cm	5'10" - 6'1"
XL	187 - 193cm	6'2" - 6'4"
XXL	194 - 201cm	6'4" - 6'7"
XXXL	202 - 209cm	6'8" - 6'10"

Inside Arm -- can be two sizes up or down from Body Width. Inside Arm is measured from armpit to wrist-bone without clothes. When you measure your inside arm let your arm hang loosely by your side. Don't extend it horizontally.

Inside Arm	cm	Inches
XXXS	41cm	16"
XXS	43cm	17"
XS	46cm	18"
S	48cm	19"
M	51cm	20"
L	53cm	21"
XL	56cm	22"
XXL	58cm	23"
XXXL	61cm	24"

N.B. PHD clothing is unisex.

Notes:

Down Jackets are sized to fit over thermal underwear & fleece.
Shell Jackets are sized to fit over thermal underwear & fleece or light down clothing (e.g. Minimus Jacket): to cover thick down clothing, go up one size.
The arms of our outdoor jackets are designed to be long enough to keep your wrists warm when your arms are extended horizontally (when using trekking poles, for example) or when you are reaching above yourself (when climbing, for example). In this respect the arm lengths of our jackets differ from street/fashion jackets.

Standard Sizing Custom Sizing Set body width, body length & arm length

Body Width

Body Length

Arm Length

Size

Outer Fabric

Hood

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Features

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
Stitch-through for lightness
Front lightweight zip with internal draft baffle
2 chest pockets (lightweight zips) above harness level
1 internal security pocket
Elasticated side panels for closer fit
Lycra cuff
Double-exit shock cord hem
Drop-tail back
Reflect for night location
Clip loop for securing
Stuff sac
Packed size: 13cm x 21cm*
Option:
- Down filled superlight zip-on hood

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

Description:

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.

The original Alpine Ultra has been acclaimed as the perfect Alpine Jacket, but it's won friends in the Himalayas too as the ideal example of light and warm. Now this K Series version is just as warm and a full 45gm lighter with all the features and capability of the original. Enough said.

Facing an early morning start, a cold wind high up, even an unexpected bivvy. Whenever you're going to need extra warmth on your peak, it doesn't come any lighter than the Alpine Ultra. It's lighter than fleece, much warmer, packs a lot smaller and has a 100% windproof outer too.

Chest pockets and a large (optional) hood allow harness and helmet use. And together with elasticated side-panels, for a closer, warmer fit, great performance is guaranteed.

Note: The optional hood needs to be ordered at the same time as the jacket.

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.

"Just want to say how impressed I am with the Alpine Ultra K series jacket. I took it to Norway this year with temps down to -15 degC, without the wind chill on top, and it was perfect. Packs as small, possibly smaller, than my waterproof jacket, lofts quickly when unpacked and is amazingly warm. I kept it in my pack, or attached to my harness (it's that small & light), and the first thing I did at every belay was put it on; bliss."
— Andy Syme.

Comments below relate to standard Alpine Ultra, which weighs 50g more

"Packs to nothing."
— Petesy (a.k.a. Peter Macfarlane).

"It's the perfect alpine downie - 330g and rated to -10 degrees - it blows the competition out of the water. Whilst the weight is awesome, you also get a tiny packed size out of it meaning that your down jacket won't eat up half your backpack space so you can go with a small backpack (20L) and keep a light and fast rhythm to your climbing."
— Jon Griffith.

"I used the Alpine Ultra Jacket as a belay jacket and emergency outer layer in the Indian Himalaya - I found it to be excellent. It's lighter and packs down smaller than any comparable jacket, and its warmth to weight ratio is second to none. There is no other jacket that I would've preferred to have with me."
— Virgil Scott - Imperial College Reru Valley Expedition (Zanskar Himalaya, India).

"Thank you for the fantastic equipment. Everything (including the Alpine Ultra 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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