Therm-a-Rest Boost 650 Short Wide Sleeping Bag 32F/0C | Backpacking Warmth

Adaptive warmth with flexible sizing

The Therm-a-Rest Boost 650 Short Wide is built to move with you. Its roomy semi-rectangular silhouette gives you the space to roll onto your side, stretch out a bit, or cozy up for a restful night. When the night turns cooler, you can transform the bag’s shape using WarmZip, a center zipper that tucks insulation around you and reduces the internal volume. This conversion can add up to 10°F (6°C) of warmth, helping you tailor comfort to the night’s conditions without changing bags.

Designed for backcountry adventures, the Boost 650 blends space and warmth with practical, user-friendly details that make camping easier. The bag’s thoughtful construction supports a natural sleeping position and simple adjustments, so you can focus on the view, the stars, or the sound of a quiet forest after a long day outdoors.

Flexible warmth and space in one bag

• WarmZip center zipper reduces internal space to boost warmth by up to 10°F (6°C).
• Inclusive sizing with Wide options accommodates broader shoulders and restless sleepers.
• Multi-use arm holes provide easy access to WarmZip, ventilation, or extended arm comfort.
• Two-way side zipper enables controlled venting around torso or feet.

Durable materials, efficient warmth

• 650-fill down is hydrophobic to stay lofted in damp conditions and zones heat where it matters most.
• Shell and liner are 100% recycled nylon with PFAS-free DWR for a lighter environmental footprint.
• YKK anti-snag pulls reduce snags and tears, keeping zippers smooth over time.
• Lightweight design (about 2 lb 2 oz / 0.95 kg) and compact packability (roughly 10 x 6.5 in / 25 x 17 cm).

In the kitchen-quiet moments of a campsite, the Boost 650’s warmth and space can feel like a personal cocoon. The combination of zoned insulation—placing heat where you need it most—and efficient compression means you stay cozy without carrying excess weight. The 100% recycled shell and PFAS-free DWR help reduce environmental impact while supporting reliable performance in mixed weather. This bag is designed for backpackers who value both adaptability and simplicity, offering a practical path to comfortable nights in variable backcountry conditions.