All the state of the science stuff employs a so called internal frame except for the heaviest loads. The internal frame is a torso adjustable padded support complete with wide padded waist band. When done right an internal frame pack is a personally fitted device. When you get a good pack and pack it right, you’ll be able to carry better than 95% of the pack’s weight on your hips. Wtih a good pack, you'll only hardly notice it's there.

I recently looked at a bunch of packs, and here’s some recommendations

Overall size: this is the storage volume of the pack. A good multiple day pack is about 3000-4000 cubic inches.

Weight varies from about 3.5 to about 7 lbs. Don’t necessarily go for the lightest one as the often don’t have features such as extra pockets, tie down straps and sockets, and a lesser frame. Note that the worse the frame the more weight you carry on your shoulders.

Features: comes down to more verses less storage areas and tie down areas. I like lots of external pockets and tie down locations. Another biggie for some is an integrated hydration pack

My pack is a Jansport Rockies 2. I love it, and spend as much time in it as I can.

Here’s some good light to mid weight packs.

Osprey packs such as the Aether 60
Granite Gear packs such as the Acadia
REI packs such as the Morning Star
Jansport packs such as the Dharma

All the heavier weight stuff is for about 6000 cu which is more suitable for long trips.

Very important to have someone show you how to fit the pack and give some guidance as to how to pack it. It will save a lot of fidgeting time on the trail.

Also echo MS comments about being prepared. I always carry a complete set of rain gear, change of clothing and, well about 20 lbs of stuff in all, and that’s just for day trips.

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...Tracy

'00 ML320 "Casper"
'92 400E "Stella"