Sea to Summit Spark -18C Down Sleeping Bag Regular beluga black

850+ fill-power down in a 10-denier shell — built for winter backcountry missions where weight and warmth both matter.

The Sea to Summit Spark -18°C is a performance mummy bag designed for cold-weather backcountry use. The fitted mummy cut maximises thermal efficiency, while box wall baffle construction throughout ensures full loft retention at the extreme end of the temperature range. RDS-certified Ultra-Dry Down provides reliable insulation even in damp conditions.

Features

• 850+ fill power RDS-certified goose down with Ultra-Dry Down treatment for improved moisture resistance

• 10D nylon shell and lining; waterproof-breathable 10D nylon hood and footbox

• Box wall baffle construction throughout for maximum loft and thermal efficiency

• 3/4-length #5 zip with zip-plow and two sliders for ventilation control

• Double draft collars seal warmth at the chest and neck

• QuiltLock system integrates with Sea to Summit quilts; pairs with women's Sea to Summit bags

Technical Specifications

• Temperature rating: Comfort -10°C / Extreme -18°C

• Insulation: Ultra-Dry Goose Down, 850+ loft, RDS-certified

• Shell and lining: 10D Nylon

• Shape: Mummy

• Body length: 185 cm (Regular)

• Packed size: 155 × 135 × 102 cm

• Weight: 1.113 kg