The F1 Mainframe represents what is arguably the greatest innovation in modern pack making, the holy grail of a great modular pack system. However, unlike any other pack system, with this loadbearing workhorse as a base, you can build a true ultra-light pack simply by adding one of our J2DB Dry Bags. The F1 is one of the primary base-platforms for the EMOD, the Eberlestock Modular System, and it works with an ever-growing number of complimentary accessories. Add components of your choice and the Mainframe can function as a freight pack, day pack, or all-around utility pack. For hunting, it transforms to a meat hauler within seconds.