This is the pack for the person who lives and breathes ultralight. Titanium tool spoons, Sil nylon tarps you know who you are! You've spent a considerable sum getting your pack weight down to 20 pounds. Now the good news your ideal pack ishere! The nylon shell gains support and rigidity from your sleeping pad simply drop in a rolled pad and let it uncoil to push against the bag, and pack your gear inside the roll. The Virga has fixed (not interchangeable), nicely padded shoulder straps and a 1.5" webbing hip belt that adjusts to fit most hips.