Modular Over Bags represent a new departure in sleeping bag technology. Built of the same materials as the Base Bags, but they literally come apart to perform many tasks...and constitute the framework for the System's name; Regulator.
Purchase them in separate sections, or as a complete stand alone bag.
In stand-alone bag mode, the ventilation is amazing - horizontally, at both the waist and the feet, and arm holes as well.
Three sections: Upper, Mid and Foot are all available separately.