High Sierra Summit 45 Frame Pack Grid-Weave Duralite 45-liter, top-load main compartment with gusseted drawstring closure and adjustable top lid. Front-load sleeping bag compartment with divider. Padded backpack straps, with adjustable load-lifters, is constructed with Vapel mesh Airflow. Molded foam back panel with Airflow&#8482 channels to keep your back cool and dry. Single, contoured aluminum frame bar can be adjusted to fit the shape of your back.