The Swiss Mountain Rucksack with two outside pockets and extendable bag is extremely durable, weatherproof and adaptable. The single outside pocket Engineers pack is much more common, but the larger 'mountain' pack is more comfortable (padded straps) and more versatile. Not a lightweight, 10 lbs empty, but ideal as an overnight pack or daypack when more gear needs to be carried, in my case fly fishing gear or predator hunting gear. It's one of the coolest and most useable military surplus packs.
