M3 is the basic platform for each member of my family's BOB. It can be carried by itself, put inside BOB rucksack or MOLLE'd to the outside of the packs. My only complaint is the hook that the zipper "handle" is attached to in not a full circle. Handles come off all the time. Been using these bags since given an issue one in 1990, and love them.
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I do the things that I must, and really regret, are unfortunately necessary.

RIP OBG