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Altitude™ Women's Down Sleeping Bag (25°F & 15°F)

This bag can take you from sea to summit

$349.00 – $419.00

Sleeping Bag Temperature Ratings Explained

The EN Rating scale is a scientific test to determine the warmth of a sleeping bag. The test produces a Lower rating (for male sleepers) and a Comfort rating (for female sleepers). Both are listed in the features table on the product page.

A unisex sleeping bag with a Lower limit of 23ºF means a man should be comfortable down to air temperatures of 23ºF. The same bag will also have a Comfort limit, in the realm of 32°F, so a woman would be comfortable down to an air temperature of 32ºF. These ratings require a sleeping mat with an R-Value appropriate for expected ground temperatures – without this, the sleeping bag itself is unlikely to keep the sleeper warm enough.

A variety of factors impact sleeping bag warmth - the above temperatures are merely guidelines, not guarantees. It’s important to think of a sleeping bag, an appropriately insulating sleeping pad and a liner as a sleep system. For example - if you plan on sleeping in nighttime air temperatures of 27ºF / -3°C, choose a bag with a gender-appropriate rating of 23°F / -5°C, plus a sleeping mat with an R-Value of 2.5 to 3, and consider a Reactor thermal liner.

$349.00
Description

Incredibly versatile, the Altitude™ women’s down sleeping bag is snug and cozy when it’s cold outside, cool and ventilated when the weather warms, shaped to match your natural sleeping position for comfort anytime, and light enough to carry anywhere.

It could just be the perfect sleeping bag for women adventurers.

Is this women's down sleeping bag…?

  • Warm enough for shoulder seasons? Yes. The high-lofting down, cozy hood and draft collar, and extra Thermolite® insulation in the foot box provide the warmth you need for cold weather. Choose the 15°F model and pair it with a Women's Comfort Light Insulated.

  • Really cool in summer temperatures? Yes. The Free-flow zipper system means separate zippers on your left and right side and in the foot box. Open them for ventilation or turn the Altitude into a fully-flat comforter.

  • Able to be zip together with another sleeping bag? The main side zipper can be zipped to many Sea to Summit Unisex sleeping bags – Regular and Long bags have the same side zipper length.

Read up on how the shape, construction and down quality of a sleeping bag will affect how well you sleep HERE

Highlights

Best Use

  • Backpacking

Performance

  • 2.5 Season: 25°F (comfort range 25°F to 70°F)
  • 3 Season: 15°F (comfort range 15° to 60°F)

Designed to keep women warm with

  • Thermolite® insulation in the foot section warms your feet instantly
  • Down chambers filled using body-mapping to maximize warmth for a woman’s physiology
  • A wider shape between hips and knees to allow you to sleep in a natural position without compressing the down insulation and creating cold spots. 
  • Shorter overall length and narrower girth in shoulders to reduce dead space and increase thermal efficiency

Features

  • ULTRA-DRY Down 750+ Loft 90% Down Cluster Premium Duck Down certified Responsible Down Standard (RDS)
  • Thermolite® insulation in the foot section warms your feet instantly
  • Free-flow zipper system: full-length YKK® #5 main side zip, half-length opposite side zip, and foot zip provides unparalleled ventilation and use as a comforter
  • Internal pocket for phone / GPS / valuables
  • Form a snug double sleeping bag by zipping to any Ascent™, Trek™ or Traverse™ sleeping bag
  • Shaped hood, oversized draft collar, and zipper draft tube keep the cold out and the warmth in
  • Includes lightweight Ultra-Sil™ compression bag and storage cell

Technical Features

750+ Loft Ultra-Dry Down™

The second highest-lofting down used in any of Sea to Summit’s sleeping bags. 750+ Fill Power indicates that one ounce (30g) of down will re-expand to over 750 cubic inches after compression. Higher loft means that less down can be used to achieve the same temperature rating – important for performance sleeping bags. The loft and down quality/composition are independently tested by the International Down and Feather Laboratory (IDFL) – a copy of the certification is supplied with every Sea to Summit sleeping bag.

 

The down is responsibly sourced and RDS certified and treated with the environmentally-friendly Ultra-Dry Down™ treatment.

 

All of which means you can rest easy.

Responsible Down Standard (RDS)

All Sea to Summit sleeping bags use only down which is certified according to the Responsible Down Standard. The RDS is helping shift the entire down and feather industry towards more humane animal rearing and handling practices. Overseen by the industry leading Textile Exchange, the RDS requires independent, third-party assessments of all aspects of animal rearing and handling throughout the entire supply chain. By using only down that meets the audited requirements of the RDS, we can have confidence that each phase of the collection process has been completed with the welfare and ethical treatment of waterfowl in mind.

To learn more about RDS, visit responsibledown.org

Thermolite® HL-1

Thermolite® HL-1 is part of the family of Thermolite® materials used in Sea to Summit sleeping bags, sleeping bag liners and sleeping mats. HL-1 high loft insulation is a fiberfill constructed with a unique 3D crimp of hollow-core and solid fibers, which provides excellent lightweight warmth with superior durability. The Thermolite insulation lofts up inside the Air Sprung Cells™ of our sleeping mats to prevent convective heat loss from your warm body to the cold ground.

Free Flow Zip

Our Free-Flow triple-zip design ensures your sleeping bag retains maximum warmth and efficiency when needed and multiple ventilation options when it's not. 

The half-zip on the right side of the bag (left side on women's bags) provides freedom of movement for both arms, additional ventilation and allows the top third of the bag to be folded down as a mini quilt when the mercury climbs higher than expected.

Tech Specs

Product Details

Best Use
Backpacking
Comes With
Ultra-Sil™ compression bag and storage cell
Insulation
Ultra-Dry Down 750+ Loft
Shell Fabric
Lightweight 20D Nylon Shell
Zip Options
Free-Flow zipper system
 
REGULAR 25°F
LONG 25°F
REGULAR 15°F
LONG 15°F
BAG SERIES
BAG WEIGHT
COMPRESSED VOL (ASTM STANDARD)
COMPRESSION SACK
FILL WEIGHT
FITS UP TO
SEASON RATING
WOMEN'S TEMP (EN RATING)
Altitude 1
2lbs 6.1oz / 1080g
6.5 L
S - 10L to 3.3L
18.3oz / 520g
5 ft 7 in / 170 cm
2.5 Season
25°F / -4°C
Altitude 1
2lbs 9.3oz / 1170g
8.3 L
S - 10L to 3.3L
20.5oz / 580g
5 ft 10 in / 179 cm
2.5 Season
25°F / -4°C
Altitude 2
2lbs 13.2oz / 1280g
8.1 L
M - 14L to 4.5L
25.4oz / 720g
5 ft 7 in / 170 cm
3 Season
15°F / -10°C
Altitude 2
3lbs 1oz / 1390g
9.8 L
M - 14L to 4.5L
28.2oz / 800g
5 ft 10 in / 179 cm
3 Season
15°F / -10°C

Customer Reviews

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