The Thermarest Boost 650 32F/0C Long is a versatile, down-insulated sleeping bag designed for backpackers and paddlers seeking adaptable warmth. Its unique WarmZip feature allows the bag to transform from a roomy semi-rectangular shape into a thermal-efficient mummy bag, increasing temperature performance by six degrees. Constructed with recycled nylon and water-repellent down, it provides reliable comfort in damp conditions while remaining lightweight and highly packable for multi-day expeditions.