Defying limits and embracing danger, the Sea to Summit Spark Down Sleeping Bag -1°C is the ultimate ultralight 2.5-season compressible sleeping bag on the market. Harnessing precision engineering and premium materials, it delivers unparalleled warmth, empowering you to conquer the elements. Perfect for those seeking a wild and weightless adventure.

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.

Pair up your Sea to Summit sleeping bag with a compatible liner for the ultimate sleep system.

More Help? For further assistance on choosing your down sleeping bag, we have an article explaining fill power, the pros and cons of down over synthetic insulation and more info on caring for your bag available to view here: .

• 850 FILL Power, RDS-certified, Goose Down with Ultra Dry Down treatment for improved water resistance in damp conditions.
  
• 10-Denier Nylon shell and lining. 10-Denier Nylon waterproof-breathable hood and footbox.
  
• Mummy Fit: Fitted cut with generous footbox and technical hood, to maximise thermal efficiency and minimise bulk and weight.
  
• Spark 7C/45F & 1C/30F Primary zip - 1/2 length #5 with zip-plow and two sliders. Spark -9C/15F & -18C/0F Primary zip - 3/4 length #5 with zip-plow and two sliders.
  
• Vertical chest baffles, horizontal baffles lower half and base. SPARK 7C sewn through quilted construction throughout. SPARK -1C/30Fbox wall baffles top half of bag and sewn through quilted construction lower half. SPARK -9C & -18C box wall baffle construction throughout.
  
• Spark 7C, -1C & -9C Standard front draft collar. SPARK -18C Double draft collars.
  
• Spark 7 & -1 can't be paired. Spark -9 & -18: Pairs with Women's Sea to Summit bags.
  
• QuiltLock: Every Sea to Summit sleeping back features the QuiltLock system that uses the snap locks located at the shoulder and foot end of Sea to Summit sleeping bags plus the quilt footbox / quilt straps to secure a quilt to the sleeping bag. This adds thermal performance and versatility to your sleep system: your integrated Sea to Summit quilt now works for ultralight summer adventures and turns your three-season bag into a four-season sleep system.
• Draft tube

• Maximum User Height:  Regular: 185cm /  - Long: 198cm
• Comfort Temperature: 4°C
• Comfort Temperature limit:  -1°C
• Shoulder width:  Regular: 155cm / Long: 165cm
• Waist With: Regular: 135cm / Long: 145cm
• Foot box width:  Regular: 102cm / Long: 112cm
• Insulated collar: Yes
• Shell Fabric: 10-Denier Nylon shell and lining. 10-Denier Nylon waterproof-breathable hood and footbox. Nylon waterproof-breathable hood and footbox.
• Filling: Ultra-Dry goose down
• Fill power: 850
• Weight: Regular: 493g / Long: 536g
• Fill Weight: Regular: 265g / Long: 305g
• Compression Size: 8L
• Zip: Left
• Draft tube