Diamir 900 Down Sleeping Bag

High-specification expedition bag, cut roomy enough for stashing kit and for comfort at altitude.

Typical Operating Temperature

-32°C / -25.6°F

Weight

1740g / 61oz

Price

£1,180.00

Full length zip (left or right) with double draft tube

I highly recommend this bag to anyone looking for a lightweight, compressible, very warm winter bag that looks like it will last for many seasons to come.
Sam Feuerborn

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Features

Exceptional 900 fillpower European Goose Down
Water-resistant Ultrashell outer fabric
Superlight MX inner fabric
Box-wall construction for max loft
Inner water-resistant panels
Full length zip protected by double draft tubes
Pack size: 25 x 44cm†
Mummy hood draws up close around head
Wide 3D Collar seals in warmth at neck
Trapezoid baffle system for ideal down control
Special baffle section stabilises down over chest
Extra down channels along each side ensure side insulation
Side block baffles prevent down shift
Ultrashell inner panels at head to protect against breath soaking the down
Ultrashell panels at inner foot to cope with damp feet/footwear
Footpiece: ovoid shape to fit naturally to feet and avoid pressure
Black inner for quick drying
Stuff sac with large mesh storage sac
Colour: Red and Gold
Options:
- Zip location: left or right
- Short or Long lengths*
- Waterproof Dri-LX outer fabric shell (+250g)‡
- Further customisation available via our Design Your Own Sleeping Bag service

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

*Please note: For all length and width options we change the amount of downfill to keep the warmth (TOT) the same.

‡Please note: The optional waterproof Dri-LX outer provides an extra seam-sealed outer shell to the bag. While a shelled sleeping bag is not designed to be used alone in heavy rain (the hood area is open to the elements) the shell does protect the bag when it is used outdoors without a tent.

Description:

This Diamir down sleeping bag takes specialised mountaineering and expedition bags to a new level with the use of PHD's exceptional 900 fill power down and inner Ultrashell panels at head and foot. The Diamir represents the benchmark for expedition down sleeping bag standards.

Cut roomy enough for comfort, and for stashing vulnerable kit overnight with you, this bag is well suited to long periods in remote camps. The trapezoid baffles provide a lightweight method of achieving excellent down control, aided by vertically-oriented chest baffles that prevent any chance of down migration.

The Ultrashell outer is highly water-repellent and helps to keep the down dry and lofting.
The Ultrashell inner panels in the hood and foot area also protect the down.
A large 3D shaped collar, side V channels to insulate the side seams, double draft tube behind the zip, and closely-boxed foot section form part of a formidable list of technical specifications.

The optional waterproof Dri-LX outer provides an extra seam-sealed outer shell to the bag. While a shelled sleeping bag is not designed to be used alone in heavy rain (the hood area is open to the elements) the shell does protect the bag when it is used outdoors without a tent, for example in a snow-hole or under a tarp.

Pictures show Diamir 1200, Diamir 900 is a little slimmer.

Dri-LX (weight: 64 gsm)

At just 64gsm, Dri-LX is our lightest 2-layer breathable waterproof rip-stop nylon fabric. Its remarkably low weight not only makes for a lighter load, but also reduces pack size. Its excellent waterproofing qualities are in part due to how it can be taped at the seams to create a waterproof shell for sleeping bags and clothing.

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.

Superlight MX fabric (weight: 32 gsm)

A mini-ripstop nylon with excellent tear strength, MX is the pick of the superfine 15 denier downproof materials. We have tested lighter fabrics, but most have had significant drawbacks, while our confidence in MX is based on several years of extensive use in both our ultralight and our high mountain gear.

900 Fillpower Down

European goose down of very high quality. A truly excellent down with large clusters, consistent quality and lively long-term performance. More on our down insulation.

Construction

PHD's trapezoid baffle system is used throughout. This is the best of the technical baffle systems, combining excellent down control with low baffle weight. In cross section the baffle system looks like this:

The design has a close-fitting down-filled mummy hood, and side V-channels which ensure all areas of the body are insulated. The baffles over the chest are vertically aligned, which stops any horizontal shifting of the down caused by arm movement during the night.

More on sleeping bag construction.

Proofed inner panels

Proofed fabric (Drishell or Ultrashell) panels are included inside the hood and foot areas of the bag to help keep the down dry. In very cold temperatures your breath can cause ice to form around the face opening, which may soak into the down as it melts. The panels at the foot end are to protect the down if you get into your bag with wet socks (or in extreme situations with your boots on).

"I spent over 90 nights in the PHD Diamir 900, and not a single one involved a shiver while sleeping. I slept in my unheated van at trailheads in the San Juans before ice climbing and ski trips; in tents in the mid-winter desert; under a blanket of stars on multi-day ski tours; and everywhere in between.

The Diamir 900's 900 fill down had an unbelievably high weight-to-warmth ratio, as one would expect. Couple that with an almost perfect fit and a waterproof outer, and this bag proved to be perfect for this past winter and for future cold weather expeditions.

I highly recommend this bag to anyone looking for a lightweight, compressible, very warm winter bag that looks like it will last for many seasons to come."
— Sam Feuerborn.

"Thank-you for the superb sleeping bag."
— Robert De Mey

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