ThermarestBoost 650 20F / -6C - Sleeping bag

In the heart of a starry mountain night, the Boost 650 from Therm-a-Rest becomes your best ally. This semi-rectangular sleeping bag offers the perfect space to move freely while staying warm. With its ingenious WarmZip system to regulate temperature, transition from a spacious cocoon to an ultra-thermal wrap in the blink of an eye. Say goodbye to cold nights, warmth is ensured thanks to its 650 fill, which adjusts to minimize the volume to heat.

The Boost 650 is not just about adaptable warmth; it is also designed for comfort and practicality. Arm openings provide unprecedented freedom: read, handle your gear, or regulate the temperature without leaving your cozy shelter. And if it gets too warm, the two-way zipper allows you to effectively ventilate the chest or feet. Every detail, from the anti-snag YKK zippers to the recycled materials, has been crafted for demanding hiking enthusiasts.

With the Boost 650, weight is no longer a concern. Its optimized design and lightweight materials make it an ideal trekking companion without compromising performance. Zoned insulation ensures targeted warmth where you need it most, while the water-repellent outer fabric and hydrophobic down protect you from the elements. Comfort, lightness, and innovation converge, making this sleeping bag much more than just an accessory: a true cocoon for all your outdoor adventures.

• Modular comfort: enjoy the freedom of movement from the semi-rectangular bag or the cozy warmth of the mummy bag: a simple zipper lets you choose the configuration and temperature that suit you best for a good night's sleep.

• WarmZip™ technology: the patent-pending central zipper reduces the bag's interior space and brings the fill closer to the body for increased warmth by up to 6 ºC/10 F.

• Multi-purpose arm openings: adjust the WarmZip system, read your book, play cards, or simply open the hatches to better regulate the temperature, all while staying comfortably wrapped in your sleeping bag.

• Cozy and comfortable: the 650 fill power RDS-certified hydrophobic down is distributed in key areas thanks to our zoned insulation technology, for optimal thermal efficiency and maximum comfort.

• Environmentally friendly materials: the outer fabric and lining are made of 100% GRS-certified recycled nylon, soft to the touch and coated with a PFAS-free water repellent.

• Sizes for everyone: Short, Standard, Long

• Additional features: anti-snag YKK zippers, hood with drawcord, zipper draft tube, draft collar, and dual-direction zipper.

• Comfort temperature: 0 °C

• Limit temperature: -6°C

• Extreme temperature: -23°C

• Fill material: 650 Fill Duck PFAS Free Hydrophobic Down, RDS

• Outer materials: 20D 100% Recycled Nylon Rip Stop