STS - SEA TO SUMMIT Spark Pro Down Sleeping Bag - RDS

Experience the uncompromising warmth, comfort, and packability of the Sea to Summit Spark Pro Down Sleeping Bag, a pinnacle of ultralight backpacking technology. Engineered for adventurers who demand the lightest weight without sacrificing performance or sleep quality, this sleeping bag redefines what it means to travel light in the wild.

Premium Insulation
Featuring 950+ fill power RDS-certified goose down, the highest lofting insulation used in any Sea to Summit bag, the Spark Pro delivers exceptional warmth-to-weight ratio. Each ounce of down re-expands to over 950 cubic inches after compression, ensuring maximum insulation with minimal bulk. The down is responsibly sourced and independently tested by IDFL for loft and quality, with every bag supplied with its certification.

Innovative Design
Wrapped in an ultra-lightweight 10D nylon shell and liner, the Spark Pro strikes a perfect balance between durability, comfort, and weight savings. The innovative Free Flow zip system provides superior ventilation, freedom of movement for your arms, and the ability to convert the top third of the bag into a mini quilt for warmer nights. Multiple zipper placements—including a half-zip for easy arm access—and quilt conversion make this bag versatile for a range of conditions from summer backpacking to cold-weather expeditions.

Responsibility & Care
100% of the down is certified to the Responsible Down Standard (RDS), ensuring ethical sourcing and animal welfare. The non-PFAS Ultra-Dry Down treatment repels moisture, absorbs less water, and dries quickly, maintaining loft and performance even in damp conditions. This treatment is environmentally friendly and lasts through at least 20 washings.

Specifications & Features

• Insulation: 950+ fill power RDS-certified Ultra-Dry Down
• Shell & Liner: 10D nylon, water repellent, non-PFAS DWR finish
• Temperature Rating: Comfort 27°F / Lower Limit 15°F (model dependent)
• Weight: As low as 1 lb 14 oz (long size, model dependent)
• Compressed Size: 7.9L (model dependent)
• Shoulder Width: 65 inches
• Hip Girth: 57 inches
• Foot Box Girth: 44 inches
• Special Features: Free Flow ZIP system, QuiltLock™ system, draft tube, zipper plow, generous mummy fit for side sleepers

Whether you’re chasing alpine summits, thru-hiking long trails, or just sleeping under the stars, the Sea to Summit Spark Pro Down Sleeping Bag is your trusted companion for exceptional warmth, comfort, and versatility—wherever your adventures take you.