A shell-less design has lower packable volume and is very light and dries quickly due to the saved material.
An extra clip on the leg loops provides a fix point for the Ice-Screws and prevents swinging while e.g. skiing.
WIREFRAME technology allows for extremely narrow and flexible hip belt and leg loops. Even without padding, the leg loops and hip belt's HDPE (high-density polyethylene) yarn processing ensures ideal weight distribution.