Ultra Down Vest: K Series

Our lightest sub-zero down vest. A 'K Series' product. Warmth to weight at the limit of possibilities for extra-keen lightweight backpackers and mountain racers. Now also available in custom sizes.

Typical Operating Temperature

-5°C / 23°F

Weight

150g / 5oz

Price

$339.61

Ultra Down Vest: K Series. Side view showing drop tail.

Ultra Down Vest: K Series. Back view showing drop tail.

For Alpine and winter stuff we use PHD's Ultra Down Vests. These are the best lightweight kit on the market.
Phil Newby, registered BAIML International Mountain Leader.

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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. A 42" (107cm) chest means that your bare chest uninflated measures 42".

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

Custom Sizing

Once you've selected a Body Width you can choose Body Length up to two sizes bigger or smaller. For example, a vest with a medium (M) Body Width can be XS, S, M, L, or XL in Body 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"

N.B. PHD clothing is unisex.

Notes:

Down and Primaloft insulated vests are sized to fit over thermal underwear & fleece.

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

Body Width

Body Length

Size

Outer Fabric

Hood

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Features

A PHD 'K Series' Product: Ultimate warmth / weight performance
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
Full width front handwarmer pocket
Stitch-through for lightness
Small zipped security pocket
Short lightweight (No.3) front zip - pullover style
Elasticated side hem
Drop-tail back
Stuff sac
Pack size: 10 x 18cm*
Options:
- Burnt Orange, Charcoal or Blue colours
- Stud on hood with Lycra edging: Adds 35grms

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

Description:

This down vest is now also available in custom sizes. Specify Body Width and Body Length independently to order a made-to-measure down vest. This tailor-made service can cope with sizes from XXXS to XXXL and is ideal if your chest/waist to height ratio differs from standard, ready-to-wear patterns.

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...

Our lightest sub-zero down vest is a genuine piece of mountain gear whose warmth will surprise you. A water-resistant outer (Ultrashell fabric) sheds moisture, while 1000 down and 10X inner fabric reduce the weight to a minimal 150gm. Warmth to weight at the limit of possibilities for extra-keen lightweight backpackers and mountain racers.

Please note: If you order a custom-sized version of this down vest it will take longer (approximately 45 days) to be manufactured ready for dispatch. Custom-sized versions of this down vest are not returnable and customer loyalty discount cannot be applied.

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.

Comments are for previous version of this vest, which weighed the same, but didn't have a water-resistant outer fabric

"For Alpine and winter stuff we use PHD's Ultra Down Vests. These are the best lightweight kit on the market."
— Phil Newby, registered BAIML International Mountain Leader.

"I bought an ultra down vest from you a couple of months ago and used it at Easter when I was camping in the Cairngorm's. I was really impressed how light and yet warm it was, despite the temperature dropping to -10 overnight and there being a couple of foot of snow!"
— John H.

"Just got my Ultra Vest. I wanted to say a big 'thank you' for designing such a fantastic piece of kit. It just felt 'right' as soon as I took it out of the parcel. I put it on (on this chilly July morning ...) and I felt immediately warmer. It is the most astonishing piece of kit I've ever owned (and I have an awful lot of stuff, let me tell ya). Beautifully designed, perfectly executed (not a stitch out of place). It's just breathtaking."
— W.P.

"So small and light that you cannot possibly not have it with you at all times! It is comfy and, when, at first I put it on I could not believe that it would keep me warm. How wrong I was. It is unnoticeable as a physical layer but highly noticeable as a warm layer. Peter Hutchinson has become a god of light and warm clothing in my book."
— Jeremy Hastings, Islay Bushcraft.

"I've been meaning to write to say what a tremendous bit of kit this Ultra vest is. I have to say the warmth to weight ratio is sensational. Top quality bit of outdoor clothing and it's been a pleasure to deal with your company."
— Mark H.

"Thanks for the Ultra vest ... a really amazing piece of kit. This must be pretty much the best warmth/weight ratio insulation piece in the world. I was glad to see your quoted weight matched the actual weights precisely. This garment is set to become an instant classic."
— Alex Haxeltine.

"Just a quick note to say I have just completed the Marathon des Sables and found your new ultravest to be the perfect wear for the colder mornings."
— John Moorhouse.

"I couldn't believe the warmth to weight performance of that little beauty [the Ultra Down Vest]. It fitted my requirements perfectly. Many thanks and congratulations on making such fantastic products."
— Edward Fowler.

"Stuffs tiny. I'm wearing it now as the heating is being weird, lovely and warm and silky."
— 'Kesh' on Live for the Outdoors forum.

"I am so pleased with it! Tested that very evening ... I was like toast, and again the vest came up trumps whilst out in the woods last weekend. Once again thank you very much for a superb bit of kit!"
— Andrew Jones.

"In a way it's a shame that the Ultra vest is as nice as it is! In the interim I'd ordered myself a Mountain Hardwear Below Zero jacket but I'm afraid that it feels second rate compared to the PHD vest. I fear that I'm going to have to return the MH and get myself a Hispar!"
— Marcus.

"Ultra Vest arrived today. It is a sensational product. Thank you for it. It was worth waiting for. Please thank the artist who made it for me!"
— Adam from Hobart, Tasmania.

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