The Sea To Summit Spark Pro 900+ Down -1°C Regular Sleeping Bag is your versatile, lightweight refuge on your next ultralight backpacking or camping adventure. Wrapped in feather-light and water-resistant 10D fabrics and filled with Sea to Summit’s 900+ fill-power highest-lofting goose down, it surrounds you with warmth that feels effortless, even as temperatures dip or tent wall condensation increases.

The premium insulation of your 2-season sleeping bag is protected by a non-PFAS Ultra-Dry Down treatment - for thermal performance you can rely on. This hydrophobic treatment resists moisture absorption and is faster drying than many alternatives.

A thoughtful mummy shape, cosy technical hood and sculpted footbox work together to lock in heat where it matters most, helping you sleep deeper and recover faster. The innovative Free-Flow Zip System transforms your sleeping bag to suit your night - unzip the various ventilation options to fine-tune airflow, or lay it flat like a quilt. 

Whether you’re unwinding in your tent after a long day on the trail or waking up to a new sunrise, this sleeping bag is built to feel like home with its lightweight, cosy comfort. 

Key Features:

• Temperature Rating (ISO Lower Limit): - 1°C | - 30°F 
• Women’s Temperature Rating (ISO Comfort): 3°C | 37°F
• Regular Length: 185cm max user height is ideal to relax comfortably and to accommodate most campers.
• Ultralight Materials, Adventure-Ready Comfort: Easy to carry in your pack during long hikes, and cocoon up at night in luxurious comfort. 
• Versatile Mummy Shape: Gives you the freedom to get into a comfortable sleeping position. 
• RDS-certified 900+ Fill-power Goose Down: The highest-lofting down from Sea To Summit for superior thermal performance, complete with non-PFAS Ultra-Dry Down treatment.
• Certified To The Responsible Down Standard (RDS): Ethically sourced and responsibly produced.
• Locks In Your Insulation: Box wall baffle structure with vertical chest baffle and horizontal baffles towards the base - ensuring the down doesn’t shift out of place. 
• Breathable And Water-resistant 10D Nylon Shell And Lining: Ultralight, ultra-soft fabric that keeps you comfortable and protected without unnecessary bulk.
• Technical Hood And Contoured Footbox: Work together to provide feather-light comfort and toasty warmth from head to toe. 
• Front Draft Collar: Generous at the shoulders and snugger at the neck for warmth retention. 
• Free-Flow Zip System: Provides personalised ventilation, and gives you the option of keeping your feet and arms free for convenience around your campsite. 
• YKK #5 Side Zipper: Smooth, reliable operation from anti-snag zipper plows - designed for durability in the outdoors.
• YKK #3 Footbox And Shoulder Zipper: Delivers weight-saving functionality. 
• Includes Compression Bag: Made of 40D recycled, bluesign approved nylon for compact carrying. 

Brand : Sea To Summit

Gender : Unisex

Shape : Mummy

Zipper Position : Left

Insulation Type : Down

Lower Temperature Limit (degrees Celsius) : 0 to -4

Temperature Rating (ISO Lower Limit) : - 1°C | - 30°F

Women’s Temperature Rating (ISO Comfort) : 3°C | 37°F

Weight : 619g | 1lb 5.8oz

Fill Weight : 310g | 10.9oz

Compressed Volume : 5.3L

Compression Sack Size : 8L

Recommended User Height : 185cm | 6 ft 1 in