A while back, the folks at Deuter invited me to review their ACT Lite 45 + 10 SL women's pack. At 3 lbs., 4 oz. it's no ultralight pack -- but hey, that's pretty light for a pack this big, and it's very light for a pack this comfortable. It also gives a nice return on structure and space in return for the weight.

Overall, I'd characterize this pack as very comfortable, stable and light. Here's what I like about it:

• Lots of comfort, structure and space in return for a little weight
• Sturdy construction
• Lots of well-thought-out features without being overbuilt

Carry Capacity

The Deuter ACT Lite 45 + 10's base carry capacity is 45 liters, or about 2,750 cubic inches. The "10" in its title refers to a fabric extension that connects the top compartment to the body of the pack. Loosen the straps holding that compartment to the pack and the extension unfolds, giving the pack another 6 inches of height and 10 liters, or 600 cubic inches, of carry capacity.

I'm not enamored of this feature because I don't like super-tall packs, but I can see how it would come in handy if you need the extra capacity but don't want to spring for an expedition-size backpack. Even without the extension, if you pack sparingly it's large enough to haul a small bearproof canister and gear for a couple of nights.

Here's some perspective on backpack sizing.

Notable Features

Here are the Deuter ACT Lite 45 + 10's most notable features, in addition to the top-compartment extension mentioned above:

• Torso sizing that's very easy to adjust with a single hook-and-loop strap. Feels secure and stable.
• Cushy padded shoulder straps and back panel, with air channels in the back that allow good airflow -- still comfortable, even on hot days. A little hook-and-loop tab keeps your hydration hose secure.
• Side pockets are nice and deep, and the side compression straps make them perfect for securely carrying trekking poles, water bottles, an avalanche probe or even a lightweight tarp setup.
• Bottom zip for easy access -- perfect for holding a small bearproof canister.
• A zip pocket in the hip belt that's roomy enough for a smartphone and car keys, a GPS unit, or a compass and folded topo map.
• Room for a 3-liter hydration reservoir.

It also has all the usual attachment points: Twin ice axe loops for climbers or winter hikers, dual trekking pole carriers, and small, corded tether points instead of daisy chains: Four on the top compartment, four on the main body.

There's also a stretchy mesh panel on the front that's meant for holding wet clothes and, believe it or not, the roomy grab loop at the top of the pack is one of my favorite features.

Other Observations

The padded hipbelt is supremely comfortable, but not overdone; in my opinion this is one of the things Deuter does best. It seats securely over your hips and in conjunction with the padded back and shoulder straps, provides a stable, comfortable ride that won't overheat you -- bliss!

The load lifter straps are easy to adjust while wearing the pack. Likewise, being able to pull the hip belt straps forward to adjust them -- instead of the back-pull straps you still find on some packs -- is very nice.

You can slide the two frame stays (which cross in an "X") out -- this is a nice feature if you need those stays to improvise a splint, or for those who want to shave as much weight as possible.

The Bottom Line

This pack is sturdy and downright cushy without feeling clunky. I don't have any really negative criticism to offer, although I would have been happy to deal with lighter-weight webbing and less-substantial zipper pulls if it shaved another ounce or two off the weight.

Disclosure: Review samples were provided by the manufacturer. For more information, please see our Ethics Policy.