I made this pack for my AK trip next month. I really wanted a ridged internal frame so I used the same curved ergonomic aluminum stays from HMG packs. I wanted a 3D mesh back panel and lumbar pad with CCF under like a Jam. There is a 12x20" CCF removable pad in front of the stays inside the pack. The shoulder and waist harness is filled with 3/4 inch GG nightlight CCF with 3D mesh over. I wanted the same mesh as a MLD Exodus with shock cord systems, and the same roll top of HMG packs. I used VX21, VX07 and dyneema X Grid. I taped the inside seams with cuben 1.0 tape for water resistance. Its about 70L and under 2 lbs.
That lump at the top is a Bearikade, those are 25" MSR Lightning Ascents