The spacious Advanced Bivy can be used in place of a single tent. It is larger than the Alpine Bivy, with more space for thicker sleeping pads and loftier bags. The patented dual-pole system can be used for increased ventilation and interior space, or left behind when weight and pack space are critical. The GORE-TEX Respiration Positive fabric allows warm moist air to escape to avoid condensation while providing supreme weather protection. A zippered vent at the base improves airflow on humid nights.