Nemo Nocturne Sleeping Bag Box Quilted: A rectangular pattern of stitching through all thicknesses of fabric, trapping down in small spaces to ensure even insulation coverage. Box Baffle: A two-way baffle system that gives a full three dimensions to each baffle and has no thin spots. This construction creates the highest loft and lowest down migration for maximum thermal efficiency. Insotect Flow Gates prevent the downwards movement of insulation, while still allowing for intentional redistribution of down Stretch Stiching: Helps maintain bag shape and loft in conjunction with NEMOs box baffle construction. It also allows the bag to subtly move with you throughout the night without bunching or binding. Dual Fill Power: Spoon Shape series bags offer backpackers adjustable comfort and weight savings with 10F less fill on the underside of the bags.