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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

Expert Pick Down Filled Water Resistant Lightweight

Scales

Packability

Ultra Compact

Compact

Mid Size

Warmth

Summer

Multi-season

Alpine

Weight

Ultralight

Lightweight

Midweight

Product Specifications

Average weight 1020g (Regular), 1157g (Long)
Compression 13 Litres (both sizes)
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

Expert Opinion

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.

Thais - Bivouac Team Member

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

Spark Pro Ultralight -9 Down Sleeping Bag

Regular packed in compression sack and held by model

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

Scales

Packability

Ultra Compact

Compact

Mid Size

Warmth

Summer

Multi-season

Alpine

Weight

Ultralight

Lightweight

Midweight

Product Specifications

Average weight 784g (Regular), 861g (Long)
Compression 13 Litres (both sizes)
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

Expert Opinion

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

Trek -9 Down Sleeping Bag

Warm, versatile and spacious bag with ULTRA-DRY Duck Down perfect for vehicle-based travels and overnight camping

Down Filled Water Resistant Recycled

Scales

Packability

Ultra Compact

Compact

Mid Size

Warmth

Summer

Multi-season

Alpine

Weight

Ultralight

Lightweight

Midweight

Product Specifications

Average weight 1436g (Regular), 1611g (Long)
Compression 20 Litres (both sizes)
Fill weight 635g (Regular), 735g (Long)
Fill ULTRA-DRY Duck Down 650+ Loft, RDS certified
Fits to 185cm (Regular), 198cm (Long)
Foot width 65.5cm (Regular), 71.5cm (Long)
Inner 20D recycled polyester with a non-PFC DWR finish
Outer 20D recycled polyester
Shoulder width 79cm (Regular), 84cm (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

Expert Opinion

Our experts haven't reviewed this product yet.

Features

Semi-rectangular fit: Spacious and generous, a roomy fit to give you room to move inside the bag, regardless of your sleeping position
Sustainable construction with 100% recycled bluesign®-approved 20D polyester shell and lining, a PFC-free water-repellent coating and RDS down
650+ Fill Power, RDS-certified, 85% Down Cluster Premium Duck Down with ULTRA-DRY Down treatment for improved water resistance in damp conditions
Free Flow Zip System for reliable, snag-free operation, to provide superior ventilation and allow the bag to be used as a comforter/quilt:
- Primary zip: full-length #5 zip with zip-plow and two sliders
- Secondary zip: half-length #5 zip with zip-plow and two sliders
- Foot box zip: #5 with two sliders
- Vertical chest baffles, horizontal baffles lower half and base, box wall baffle construction throughout
- Shaped hood and oversized zip draft tubes to seal in warmth and keep cold out
- Fitted front draft collar: scalloped over the neck and oversized at the shoulders.
- Internal pocket for phone / GPS / valuables
- QuiltLock System allows Sea to Summit quilts to be locked into place over the top of the Trek, giving you modular and versatile sleeping bag
- Form a snug double sleeping bag by zipping to any women's Sea to Summit sleeping bags
- Includes lightweight Ultra-Sil compression bag and storage cell

Sea to Summit

Spark Ultralight 7 Down Sleeping Bag

Lightweight down mummy-shaped bag

Expert Pick Down Filled Water Resistant Lightweight

Scales

Packability

Ultra Compact

Compact

Mid Size

Warmth

Summer

Multi-season

Alpine

Weight

Ultralight

Lightweight

Midweight

Product Specifications

Average weight 363g (Regular), 387g (Long)
Compression 2 Litres (Regular), 3 Litres (Long)
Fill weight 150g (Regular), 170g (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 11°C comfort rating woman / 7°C Lower comfort rating for men; Temperature rated in accordance with ISO 23537-1:2022

Expert Opinion

Performance and Comfort in a Lightweight Package

"The Spark 7 is one of the more compact sleeping bags on the market. It is really comfortable with the 3/4 zip and even the little features of the plastic flaring that goes over the zip to stop it from catching the fabric and making it more comfortable for sleeping. I find while this bag is rated to 7 degrees, with a small amount of clothing on during the night it is quite comfortable down to 5 or 6 degrees overnight temps."

Braden Currie - Endurance Athlete

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
Half-length #5 zip with anti-snag zip plow and two sliders
Vertical chest baffles, horizontal baffles in the lower half and base, sewn-through baffle construction throughout
Technical fitted hood with soft touch adjustment, extra deep for cosy-like feel
No draft tube
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