Therm-a-Rest Boost 650 Sleeping Bag

The Therm-a-Rest Boost 650 is a three-season down sleeping bag for backpackers and campers who want adjustable comfort and warmth in a lightweight package. Its convertible design lets you trade space for insulation as conditions require.

Key features

• WarmZip™ convertible zipper: turns the rectangular bag into a mummy shape, increasing warmth by up to 6 °C.
• 650‑fill hydrophobic down: RDS‑certified down arranged in zoned insulation for efficient warmth where needed.
• Recycled nylon shell and liner: 100% recycled nylon with a PFAS‑free DWR finish.
• Multi‑use hand openings: access, ventilation and reach without leaving the bag.
• Comfort details: puffy draft collar, zipper draft tube and YKK anti‑snag two‑way side zipper.

Suitable for backpacking and car camping in spring to autumn conditions. The bag ships with a compression sack and a storage sack for packing and offseason storage.