Therm-a-Rest Boost 650 20F/-6C Small Morning Blue

Comfort doesn't come in a one-size-fits-all, which is why the shape of the Boost 650 can be individually adjusted to find the perfect balance between freedom of movement and warmth. As a spacious, semi-rectangular sleeping bag, the Boost provides ample room for side sleeping, turning over, stretching out, and relaxing. The semi-rectangular shape offers significantly more space inside than a mummy sleeping bag – you feel free and can sleep in any position you desire throughout the night. However, more space requires more body heat to keep warm. This is where the WarmZip comes in. With the high-cut zipper, the shape of the Boost 650 transforms from a semi-rectangular sleeping bag into a heat-efficient mummy sleeping bag. This redistributes the down around the body and reduces the space needed for warmth. With the WarmZip, the thermal performance of the Boost can be increased by up to 6 °C. Standard features from Therm-a-Rest include a lofty design.