THIS PACK IS AWESOME!! Eberlestock F1 Mainframe Review - The F1 Mainframe by Ebelestock is great.

The Eberlestock F1 Mainframe is an external frame pack that excels as a meat hauler. The Mainframe has great adjustability and is part of Eberlestock's modular system. You can attach different duffels - Super Spike or Spike Camp, the Dry Bag, and various accessory pouches utilizing the MOLE webbing. I found this pack to be extremely comfortable and able to handle a lot of weight. This is a great pack for Western Big Game Hunting - Elk, Moose, Mule Deer, Etc. I have also found it to be a good daypack when used with the Eberlestock A6SB Batwings.