Therm-a-Rest Boost 650 -6°C Down Sleeping Bag

Shape-Shifting Warmth to –6 °C

Master three-season comfort with the Boost 650™ –6 °C Down Sleeping Bag. Its WarmZip™ center zipper toggles between a spacious semi-rectangular bag and a snug mummy shape, boosting insulation by up to 6 °C on demand. Zoned 650-fill RDS-certified hydrophobic down keeps your core, shoulders, and feet toasty, while arm holes, draft tube, cinchable hood, and anti-snag YKK zippers deliver customizable comfort from car camp to alpine missions. Made with 100 % recycled nylon shell and liner treated with PFAS-free DWR, it packs light, sleeps big, and performs down to –6 °C.

Therm-a-Rest Boost 650™ –6 °C Sleeping Bag Features

• WarmZip™ Adaptability: Toggle between semi-rectangular and mummy shapes to add up to 6 °C of warmth.
• 650-Fill Zoned Down: RDS-certified hydrophobic down precisely placed around core, shoulders, and footbox for optimized warmth-to-weight.
• Multi-Use Arm Holes: Ventilate, access the WarmZip™, or cocoon yourself without fully unzipping.
• Premium Comfort Details: Cinchable hood, insulated draft tube and collar, and YKK anti-snag two-way zipper for a snug, adjustable fit.
• Sustainable Materials: 20D recycled nylon shell and liner with PFAS-free DWR for lightweight durability.
• Inclusive Sizing: Available in Small, Small Wide, Regular, Regular Wide, Long, and Long Wide to fit every sleeper.
• Complete Carry System: Compression sack for travel and roomy storage sack for long-term care.

Therm-a-Rest Boost 650™ –6 °C Sleeping Bag Specifications (Metric)

• Temperature Rating (EN): Comfort –1 °C; Limit –6 °C; Extreme –20 °C
• Fill Material: 650-fill duck PFAS-free hydrophobic down (RDS certified)
• Shell & Liner: 20D 100 % recycled nylon ripstop with PFAS-free DWR
• Zipper: Side-entry, left-hand YKK anti-snag
• Color: Meadow Green
• Country of Origin: Vietnam