Experience versatile comfort that adapts to your adventure with the Therm-a-Rest Boost 650 Down Sleeping Bag. This ingeniously designed bag transforms from a spacious semi-rectangular shape for unrestricted sleeping to a snug mummy configuration using the innovative WarmZip centre zipper—adding up to 10°F of warmth when temperatures drop. Strategically placed arm holes let you stay cosy whilst accessing gear, reading, or simply ventilating when needed. Built for backpackers who refuse to compromise, the Boost combines 650-fill hydrophobic down with zoned insulation and 100%-recycled nylon to deliver exceptional warmth without the bulk. Weather-resistant and remarkably packable, this is the sleeping bag that grows with your needs, whether you're car camping or tackling remote trails.
Features:
- Ultra-comfy three-season backpacking sleeping bag with adjustable shape and warmth.
- Customizable Comfort: Enjoy the spacious freedom of the semi-rectangular bag or the cozy warmth of a mummy bag—pick the shape and temperature that keeps you comfy at night with just a zip.
- WarmZip™ Tech: Patent-pending centre zipper design zips up to reduce the bag’s internal space and tuck insulation around the sleeper to boost warmth by up to 10F/6C.
- Multi-Use Arm Holes: Reach the WarmZip, read a book, play cards or simply ventilate—do it all while tucked into your sleeping bag for elevated liveability.
- Plush & Puffy: 650-fill RDS-certified hydrophobic down is allocated to key areas with Zoned Insulation for refined heat efficiency and maximum coziness.
- Eco-Conscious Materials: Shell and liner are made of GRS-certified 100% recycled, soft-to-the-touch nylon and coated with PFAS-free water repellent.
- Inclusive Sizing: Each size—Small, Regular, Long—is also available in a Wide size, so you get the bag you want in the fit you need.
- Additional Features: YKK anti-snag zippers, cinchable hood, zipper draft tube, puffed draft collar, and a two-way entry zipper.
- What's Included: Compression Sack, Storage Sack
- Weight: 952g
- Comfort: 5°C, Limit: 0°C, Extreme: -15°C
- Fits: 183cm
- Girth Shoulder: 160cm, Girth Hip: 152cm, Girth Footbox: 155cm
- Packed Dimensions: 25 x 17 cm
- Fill material: 650-Fill Duck PFAS-Free Hydrophobic Down, RDS
- Shell and Lining: 20D 100% Recycled Nylon Rip Stop