MB Super Critical Mass Alpine II
The MB Super CM Alpine II is an expedition pack that also works great for extended backpacking. These packs are custom made to your specifications. Pack features include a unique shoulder strap system and hip belt. The pack has a U-shaped internal frame, not just stays. The top 8" or so of the frame is a removable bayonet that allows you to trim the pack for smaller loads. The basic pack is no frills and light. You can order the pack with a wide variety of options, including hydration sleeves, exterior pockets and essentially anything that can be sewn on. Choose your fabric based on weight and durability.
Visit the McHale website for complete details and the full range of comparable packs.