Thermarest Boost 650

• 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 center 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 livability.
• 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 length—Short, Regular, Long—is also available in a Wide width, 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