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Sea to Summit

Spark Pro Ultralight -9 Down Sleeping Bag

Lightweight and functional bag that is optimised for comfort and versatility on lightweight adventures

Down Filled Lightweight

Select options

Scales

Packability

Ultra Compact

Compact

Mid Size

Warmth

Summer

Multi-season

Alpine

Weight

Ultralight

Lightweight

Midweight

Product Specifications

Average weight 784g (Regular), 861g (Long)

Fill weight 480g (Regular), 550g (Long)

Fill ULTRA-DRY Goose Down 900+ Loft, RDS certified

Fits to 185cm (Regular), 198cm (Long)

Foot width 51cm (Regular), 56cm (Long)

Inner 10D nylon with a non-PFC DWR finish

Outer 10D nylon

Shoulder width 77.5cm (Regular), 82.5cm (Long)

Temp rating minus 3°C comfort rating woman / minus 9°C Lower comfort rating for men; Temperature rated in accordance with ISO 23537-1:2022

Compression 13 Litres (both sizes)

Trusted Opinions

Our experts haven't reviewed this product yet.

Features

• Mummy Fit: Fitted cut with generous anatomical footbox and technical hood, to maximise thermal efficiency and minimise bulk and weight
• bluesign®-approved 10D nylon shell and lining fabric offers breathability, protection and effective temperature regulation for premium comfort in the outdoors
• 10D nylon's waterproof and breathable features offer added protection and prevents exposure to tent wall condensation
• 900+ Fill Power, RDS-certified, Goose Down with ULTRA-DRY Down treatment for improved water resistance in damp conditions
• Free Flow Zip System for reliable, snag-free operation and minimal weight:
  • Primary zip: full-length #5 with zip-plow and two sliders
  • Secondary zip: 1/4-length #3 with zip-plow and two sliders
  • Footbox zip: #3 with two sliders
• Vertical chest baffles, horizontal baffles in the lower half and base, box wall baffle construction throughout
• Technical fitted hood with soft touch adjustment, extra deep for cosy-like feel
• Fitted front draft collar: scalloped over the neck and oversized at the shoulders
• Pairs with women's Sea to Summit bags and the QuiltLock System allows integration with Sea to Summit quilts
• Comes with an Ultra-Sil compression bag and a storage cell

Sea to Summit

Ascent -9 Regular Down Sleeping Bag

Designed for comfort and adaptability and suited to a wide range of adventures in cold conditions

Down Filled Water Resistant Lightweight

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Scales

Packability

Ultra Compact

Compact

Mid Size

Warmth

Summer

Multi-season

Alpine

Weight

Ultralight

Lightweight

Midweight

Product Specifications

Average weight 1020g (Regular), 1157g (Long)

Fill weight 540g (Regular),617g (Long)

Fill ULTRA-DRY Goose Down 750+ Loft, RDS certified

Fits to 185cm (Regular), 198cm (Long)

Foot width 59.5cm (Regular), 64.5cm (Long)

Inner 20D recycled polyester with a non-PFC DWR finish

Outer 20D recycled polyester

Shoulder width 78cm (Regular), 84cm (Long)

Temp rating minus 2°C comfort rating woman / minus 9°C Lower comfort rating for men; Temperature rated in accordance with ISO 23537-1:2022

Compression 13 Litres (both sizes)

Trusted Opinions

Staff (1)

Thais Bivouac Team Member

If you are looking for a very decent quality sleeping bag that is lightweight but don't want to give up on comfort, the Sea to Summit Ascent range is a fantastic place to look!

Though the shape of the bag still tapers at the bottom, the sleeping bag is much more rectangular than most mummy bags. The Free-Flow zip provides flexibility with temperature adjustment whether you want to use you bag as a quilt, stick your feet out or stick out your arms to read a book. The high quality 750+ down fill allows this bag to remain decently lightweight while still performing in cold temperatures. When going with a higher warmth rating like the -9 it usually means you might be using it on colder, longer nights where comfort will be key to a good sleep. The -9 would be a good choice for someone going on adventures all year long.

Fit tip:

Nice and roomy, good for side sleepers or people who tend to move around in their sleep.

Trusted Opinions

Staff (1)

Thais Bivouac Team Member

If you are looking for a very decent quality sleeping bag that is lightweight but don't want to give up on comfort, the Sea to Summit Ascent range is a fantastic place to look!

Though the shape of the bag still tapers at the bottom, the sleeping bag is much more rectangular than most mummy bags. The Free-Flow zip provides flexibility with temperature adjustment whether you want to use you bag as a quilt, stick your feet out or stick out your arms to read a book. The high quality 750+ down fill allows this bag to remain decently lightweight while still performing in cold temperatures. When going with a higher warmth rating like the -9 it usually means you might be using it on colder, longer nights where comfort will be key to a good sleep. The -9 would be a good choice for someone going on adventures all year long.

Fit tip:

Nice and roomy, good for side sleepers or people who tend to move around in their sleep.

Features

• Relaxed Mummy Fit: A more relaxed yet tapered mummy fit with high thermal performance
• Lightweight 100% recycled 20D nylon shell with a non-PFC DWR finish to protect against wind and moisture and a 20D recycled nylon liner for greater comfort
• bluesign®-approved fabrics
• 750+ Fill Power, RDS-certified, Goose Down with ULTRA-DRY Down treatment for improved water resistance in damp conditions
• Free Flow Zip System for reliable, snag-free operation and minimal weight:
  • Primary zip: full-length #5 with zip-plow and two sliders
  • Secondary zip: 1/2-length #3 with zip-plow and two sliders
  • Footbox zip: #5 with two sliders
• Vertical chest baffles, horizontal baffles in the lower half and base, box wall baffle construction throughout
• Generous fitted hood with two soft touch adjustments and fits a Sea to Summit regular pillow
• Fitted front draft collar: scalloped over the neck and oversized at the shoulders
• Single, down-filled draft tube along the top of zips
• Internal pocket for phone / GPS / valuables
• Pairs with women's Sea to Summit bags for a snug double sleeping bag
• QuiltLock System allows integration with Sea to Summit quilts
• Comes with an Ultra-Sil compression bag and a storage cell

Sea to Summit

Spark Ultralight -9 Down Sleeping Bag

Lightweight down mummy-shaped bag for cold conditions

Down Filled Water Resistant Lightweight

Select options

Scales

Packability

Ultra Compact

Compact

Mid Size

Warmth

Summer

Multi-season

Alpine

Weight

Ultralight

Lightweight

Midweight

Product Specifications

Average weight 730g (Regular), 786g (Long)

Fill weight 480g (Regular), 540g (Long)

Fill ULTRA-DRY Goose Down 850+ Loft, RDS certified

Fits to 185cm (Regular), 198cm (Long)

Foot width 51cm (Regular), 56cm (Long)

Inner 10D nylon with a non-PFC DWR finish

Outer 10D nylon

Shoulder width 77.5cm (Regular), 82.5cm (Long)

Temp rating minus 2°C comfort rating woman / minus 9°C Lower comfort rating for men; Temperature rated in accordance with ISO 23537-1:2022

Compression 13 Litres (both sizes)

Trusted Opinions

Staff (1)

Thais Bivouac Team Member

If your goal is to transition into more lightweight gear and carry less bulky items, then start with your sleeping bag. The Sea To Summit Spark series are the best lightweight to warmth ratio we stock in our store. The face fabric is only 10D which is why you can see the 850+ down through it and allows the sleeping bag to compress into a tiny bag. The -9c model is a great option if you are looking for a 3-season sleeping bag or even 4-seasons if you sleep warm and don't mind adding a couple of layers. I would use this bag anytime between late winter to beginning of winter if camping and all the way through NZ winter if hutting. The baffles by the torso area have been designed vertically so that the down stays in place when moving around to stop any cold spots.

Something to keep in mind is that due to the face fabric being so thin, this would not suit someone who is sleeping in harsh conditions and is rough with their gear. The mummy shape is very tapered and could feel restrictive for people who like to move around in their sleep and the zips don't unzip all the way around. Keep in mind those things when considering this model, but you will need to make some compromises if wanting to transition to lightweight gear.

Fit tip:

Tapered mummy shape

Trusted Opinions

Staff (1)

Thais Bivouac Team Member

If your goal is to transition into more lightweight gear and carry less bulky items, then start with your sleeping bag. The Sea To Summit Spark series are the best lightweight to warmth ratio we stock in our store. The face fabric is only 10D which is why you can see the 850+ down through it and allows the sleeping bag to compress into a tiny bag. The -9c model is a great option if you are looking for a 3-season sleeping bag or even 4-seasons if you sleep warm and don't mind adding a couple of layers. I would use this bag anytime between late winter to beginning of winter if camping and all the way through NZ winter if hutting. The baffles by the torso area have been designed vertically so that the down stays in place when moving around to stop any cold spots.

Something to keep in mind is that due to the face fabric being so thin, this would not suit someone who is sleeping in harsh conditions and is rough with their gear. The mummy shape is very tapered and could feel restrictive for people who like to move around in their sleep and the zips don't unzip all the way around. Keep in mind those things when considering this model, but you will need to make some compromises if wanting to transition to lightweight gear.

Fit tip:

Tapered mummy shape

Features

• Mummy Fit: Fitted cut with generous anatomical footbox and technical hood, to maximise thermal efficiency and minimise bulk and weight
• bluesign®-approved 10D nylon shell and lining fabric offers breathability, protection and effective temperature regulation for premium comfort in the outdoors; PFC-free DWR (durable water repellent) treatment keeps the hood and footbox highly water resistant
• 850+ Fill Power, RDS-certified, Goose Down with ULTRA-DRY Down treatment for improved water resistance in damp conditions
• 3/4-length #5 zip with anti-snag zip plow and two sliders
• Vertical chest baffles, horizontal baffles in the lower half and base, box wall baffle construction throughout
• Technical fitted hood with soft touch adjustment, extra deep for cosy-like feel
• Standard front draft collar
• Single, down-filled, draft tube along the top of zips
• Pairs with women's Sea to Summit bags and the QuiltLock System allows integration with Sea to Summit quilts
• Comes with an Ultra-Sil compression bag and a storage cell
• Ultralight does not mean ultra-tight: The Spark mummy sleeping bags are snug but still have adequate wiggle room for the performance-oriented, backcountry user

Exped

Ultra minus-10-Degree Down Sleeping Bag

Compact, duck down sleeping bag for ultralight adventures in colder conditions

Select options

Scales

Packability

Ultra Compact

Compact

Mid Size

Warmth

Summer

Multi-season

Alpine

Weight

Ultralight

Lightweight

Midweight

Product Specifications

Average weight 1110g (Medium), 1170g (Long)

Fill weight 700g (Medium), 730g (Long)

Fill 850+ cuin/oz Muscovy Duck Down| RDS certified| OEKO-TEX® 100 certified

Fits to 180cm (Medium), 195cm (Long)

Foot width 48cm (Medium), 49.5cm (Long)

Inner Recycled 15D ripstop nylon, OEKO-TEX® 100 certified, DWR free, no intentionally added PFAS

Outer Recycled 10D ripstop nylon, bluesign® approved, no intentionally added PFAS

Shoulder width 74cm (Medium), 75.5cm (Long)

Temp rating minus 2°C (Comfort) minus 8°C (Limit) minus 26°C (Extreme)

Length 203cm (Medium), 218cm (Long)

Rolled size 25 x 22 x 17cm / 9.3 Litres (Medium) 26 x 22 x 17cm / 9.7 Litres (Long)

Trusted Opinions

Our experts haven't reviewed this product yet.

Features

• Outstanding warmth-to-weight ratio
• Hardwearing 100% recycled nylon outer and inner fabrics
• High-quality, durable, RDS-certified Muscovy Duck down insulation
• Lightweight and compact design
• Thick draft tube provides excellent heat retention
• Side cover strip along the zip reliably prevents cold bridges
• Adjustable drawstring hood and elliptical thermal collar minimise draft and heat loss
• Proportional differential cut (liner is shaped smaller than the shell) for optimal down lofting and comfort
• 3D footbox with 11 individual down-filled baffles eliminates cold spots and allows natural leg movement
• Footbox pocket
• Anti-snag zip for smooth zip operation and large zip garage to keep zip away from your face
• Glow-in-the-dark zip pulls
• Bartack reinforcements where necessary for enhanced durability
• Two-way zips increase flexibility and allow for temperature regulation
• Easy-access internal pocket for phones, headlamps, and essential items
• Comes with a roll-top waterproof stuff sack and mesh storage bag
• Part of Exped's Fast and Light Series
• This product meets bluesign® product requirements, which means materials and components have been selected that adhere to rigorous environmental and social criteria during production
• Exped calculates all climate emissions from the production and transportation of this product and finances certified climate protection projects through myclimate to an equal extent

Spark Pro Ultralight -9 Down Sleeping Bag

Ascent -9 Regular Down Sleeping Bag

Spark Ultralight -9 Down Sleeping Bag

Ultra minus-10-Degree Down Sleeping Bag