A Great Backcountry Sleeper: The Feathered Friends Lark 10 UL Sleeping Bag

Ultralight, ultra-warm, and ultra-packable. The Lark 10 UL from Feathered Friends is a powerhouse of a sleeping bag for backcountry hunters, hikers, and campers.

As an avid backpack hunter, I’m always on the search for quality gear to improve my backcountry system. These pieces of gear need to be ultralight, packable, and reliable. When you’re in the backcountry, you’ve got what you’ve got, and that’s that.

Sleeping bags are one of the main items I pay attention to improving upon, especially when the temps drop. When I got word of the Lark 10 UL from Feathered Friends, I knew I just had to put it to the test in the mountains. On paper it was perfect.

Time would tell if it lived up to its specs, though.

A Closer Look at the Lark 10 UL

Before getting into the review, let’s take a closer look at the Lark 10 UL. This 10-degree mummy-shaped bag comes in both regular (6 feet) and long (6.5 feet) models and is filled with 950+ goose down. Regular models come in at 31.3 ounces, and long models sit at 33.1 ounces, which makes for an excellent warmth-to-weight ratio.

Pertex Endurance UL is the material used on the shell of the Lark. This is a water-resistant, breathable material that will aid in beading off condensation in the field. Wet down is extremely hard to dry, so this is a welcome addition.

The Lark also comes equipped with #5 YKK two-way zippers with locking sliders. Subpar zippers are never fun to deal with and Feathered Friends knows that. Along with the bag, you’ll get a stuff sack for packing as well as a storage sack for stowing the bag away at home when not in use.

My Favorite Features of the Lark 10 UL

Collar and Zipper

Two of the first things that stuck out to me with the Lark 10 UL were the collar and zipper. The collar is fantastic at trapping heat in the bag, and I mean fantastic.

On a recent backcountry spring bear hunt, never once did I feel air creeping in from the top of the bag. This was a common occurrence for me with other bags in the past.

And then there’s the zipper. I’ve always had issues with zippers snagging, and Feathered Friends has seemed to solve that with their zipper slides and zip guard. The slides help reduce the chance of fabric snagging while the guard — a flexible piece of plastic inside the fabric — helps guide the fabric away from the zipper.

Roomy

I’m a side sleeper and have always had some issues with traditional mummy bags. They usually don’t provide the space for me inside the bag to comfortably turn onto my side without turning the whole bag with me.

This is another area I’ve been pleasantly surprised with the Lark 10 UL. Sure, it is indeed a mummy-shaped bag, but they’ve given the user a bit more room.

I can comfortably turn on my side within this bag and don’t feel like I’m being strangled by it. For reference, I’m 5’11” and went with the regular-size bag.

Even Warmth

This bag is not just comfortable, but it also offers evenly distributed warmth. So far, I’ve spent 20 days sleeping in the Lark 10 UL.

I haven’t experienced cold spots, at all. I believe this is due to the extremely high-quality down, as well as the continuous baffles that let you position the insulation where you need it. I haven’t had to do so personally, but the option is there.

A Few Downsides

Even though I’ve been very happy with the Lark 10 UL, there are a few downsides. The biggest one on the surface is the price of this bad boy. For a regular size, you’ll pony up $609 and for a long size, it’ll set you back $629. That’s a hefty pill to swallow for a sleeping bag.

But on the plus side, a down sleeping bag cared for correctly can last for decades. That big price tag comes with the assurance of literally years of good sleep, which makes the medicine go down a lot easier.

And while the packability is impressive on this bag, it can always be better. Down quilts have been my go-to for many years, due to their smaller packed size.

It would be nice if Feathered Friends offered a compression sack instead of a regular stuff sack. This would help immensely when it comes time to pack up and wouldn’t require one to buy one separately.

Final Thoughts

At the end of the day, I really love this bag. From its functionality to its build quality, this thing can handle whatever is thrown at it. It’ll do so without lacking in performance as well. Sure, there are some downsides like anything, but you can bet your rear end this sleeping bag is gonna do what you need it to.

Reliability is heavy on the list of importance when it comes to gear for me. As someone who spends more than a fair amount of time backcountry hunting, this is definitely a piece of gear that has earned a spot in my pack. I’m looking forward to more adventures with my Feathered Friends Lark 10 UL Sleeping Bag!

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