Sea To Summit Venture Women's Synthetic Sleeping Bag RegularOur unique WaveLoft construction uses thick layers of THERMOLITE insulation looped together to gain extra loft and trap pockets of warm air, providing increased warmth in colder conditions. The baffle construction also eliminates the frustration of getting tangled in loose lining as all lining fabrics are attached to the shell fabric. The Venture also features thicker insulation in the footbox, reducing the chance of cold feet interrupting your nights