Premium 4-Season Warmth for Extreme Conditions and Adventures

When the temperature drops and comfort matters most, the Therm-a-Rest Questar 0F / -18C Down Sleeping Bag delivers reliable warmth and performance for serious winter camping and cold-weather backpacking. Designed for four-season use, this feature-packed sleeping bag combines water-resistant 650 fill Nikwax Hydrophobic Down with advanced comfort technology to keep you warm, dry, and well-rested in frigid conditions.

Therm-a-Rest Questar 0F / -18C comes complete with a compression sack for efficient packing and a storage sack for long-term care.

Perfect for alpine expeditions, winter wild camping, or year-round adventures—the Questar 0F is built to deliver serious warmth and dependable comfort wherever the trail takes you.

Explore our full range of Down Sleeping Bags here.

FEATURES OF THE THERM-A-REST QUESTAR 0F/-18C SLEEPING BAG

650 Fill Nikwax Hydrophobic Down: Absorbs 90% less water and dries 3x faster than untreated down—without harmful PFCs. Certified by the Responsible Down Standard (RDS) for ethical sourcing.
W.A.R.M. Fit (With Additional Room for Multiple Positions): Engineered in Therm-a-Rest’s onsite cold chamber, this ergonomic shape offers extra space for natural sleeping positions while maintaining superior thermal efficiency.
SynergyLink™ Connectors: Removable ultralight straps securely attach your sleeping bag to your sleeping pad, maximising warmth and comfort across your entire sleep system. Works best with pads up to 3 inches thick.
Zoned Insulation: Strategically placed down maximises warmth where you need it most and saves weight for efficient packability.
Box-Baffled Construction: Mesh walls enhance loft and eliminate cold spots for consistent insulation.
Ergonomic Toe Box: Specifically shaped to rapidly warm cold feet within a pocket of insulated down.
Quilt & Blanket Loops: Easily layer Therm-a-Rest quilts or tech blankets for customisable warmth.
Comprehensive Cold-Weather Design: Includes a heat-trapping draft collar, full-length zipper draft tube, snag-free zipper, cinchable hood, and external zip pocket for essentials.

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Sierra Designs Nitro 0 Deg Down Sleeping Bag Comfort Rating -9°C

Therm-A-Rest Questar 0F/-18C Down Sleeping Bag

Nortent Lyng -20 °C Down Sleeping Bag