Feathered Friends - Tanager 20 CFL

I paid $1k for a -40 degree sleeping bag. Because the -20 degree sleeping bag I bought the year before wasn’t warm enough. Feathered Friends. They are $1,200k now. Alaska is cold in March.

Yeah, basically. I have the Feathered friends tanager that's a zipperless sleeping bag, and the Cumulus Aerial 180 (similar to the model you're asking about, but lighter/no hood). Can't fold open like a quilt, but no zipper means less weight, and being totally enclosed means no drafts. I sleep cold, so I rarely would want to stick a foot out of a quilt or open it up, and the false bottom saves weight. All comes down to preferences. With the Tanager and Aerial, I've never minded wiggling in/out, but YMMV.

(Edit: sorry about the over the top click bait title!) Ok… If you know me, my gear system is about maximizing comfort but still decreasing weight. Quilts have been a part of that system since 2017, but in 2025 they fail me in too many ways. 1)      Quilt straps are undeniably annoying. They get tangled, lost, they take time to position. It’s management time and I am lazy. I would rather watch that sunset, eat or just do nothing. 2)      Yes, a quilt reduces weight by removing unneeded backside material. However, because of the hole in the backside of a quilt, you must add back in straps, clip hardware, & hem reinforcement weight. Some manufactures even add tensioning systems to limit cold air ingress. It’s never made much sense to punch a big hole in something, only to add in weight in response to you punching a big hole in something. 3)      Quilts promise weight savings by eliminating traditional sleeping bag hoods, zippers, zipper guard tape, a draft tube backing up the zipper, and no unnecessary backside fabric/down. But, there’s a way to eliminate the first 4 of those and I’m going to show you why you actually WANT that backside fabric/down. 4)      Cold Drafts. I’m not saying drafts are overly frequent, but through the years they’re just not welcome anymore. I’ve heard deep ultralighters (sub 6lbs) talk about how they have trained themselves to just lay on their back all night. That is not how sleep is supposed to work. It’s good to toss and turn to keep blood moving through your tissues. However, when you toss and turn, air can make its way in. At 35F/2C or colder, it’s going to wake me up %100 of the time. Maximizing comfort means eliminating things that wake me up. There’s a better way to do this. But first, let’s address the number one advantage of quilts. Venting! You can loosen them and drape them over your body on a hotter night. There’s no disputing this great feature. However, if I am on a 5 day trip, maybe one of those nights may be “too” warm. I usually choose the right rating for the trip I am on. If more than 3 nights are excessively warm for the quilt, then I just brought the wrong gear. Thru hikers don’t have this luxury, but more on that in a second. The better way to stay warm, but not too warm, and still ultralight is… A simple hoodless and zipperless bag like the Nunatak Sastrugi (I have 2,) Feathered Friends Tanager, and now the Gryphon Gear Full length Elephant Bag (I just got a 40F/4C for hut hiking this summer.) [Go look at the Tanager right now](https://featheredfriends.com/products/tanager-cfl-20-ultralight-down-sleeping-bag?variant=20318841471030&country=US¤cy=USD&utm_medium=product_sync&utm_source=google&utm_content=sag_organic&utm_campaign=sag_organic&gad_source=1&gclid=CjwKCAiAn9a9BhBtEiwAbKg6fltZJpD6HJWLTnxsXD_uEcHtoU52V_jPJd9RXhcKx_4exF-d9fkTARoCoocQAvD_BwE) if you don’t know what I am talking about. It is NOT a traditional hoodless sleeping bag. It’s a simple bag that you slide your entire body, feet first, through the top opening. There is NO zipper and both the top and backside of the bag are the same. In other words, what you see on the top is what you see on the back (more on that in a moment.) This is what I have started to use and I like it… 1)      It’s cheaper to build, like $100 cheaper. 2)      There are no back side drafts because there’s no backside opening 3)      There are way fewer things to fail/tangle/lose/manage 4)      When you sit up on a cold morning, the bag is covering your back as you get ready for the day (thanks u/laurk) 5)      You still get the weight savings of no hood, no zipper, no zipper tape, and no zipper draft tube. 6)      But, here’s **THE BEST PART**, you get two different temperature ratings in one bag! You may not know this, but a lot of bag makers put a little less down in the back than on the top (that or you can shift the down with continuous baffles.) Some even change the baffle height (i.e. the loft) from top to back. Gary at Gryphon Gear confirms this on my new full length Elephant Foot bag. The topside baffle height is 0.4in higher than the back side. So, it’s indeed a two temperature sided bag. Here's what my testing has found. The 28F/-2C Nunatak Sastrugi is accurately rated on the topside. Now then, with the backside moved to sitting on top of my supine body, it's roughly good till 37F/3C, with the neckline cinched. Then, if I purposely move down to the side, it turns into 42F/5.5C (neckline is again cinched) and if I uncinch the neckline I’m good to about 48F/9C. At 48F/9C my feet start getting a little warm, as it's really tough to move down out of either side of a foot box. Note: I'm just wearing a tee shirt and short underwear. I'm also in a higher humidity area, just off a cold ocean delta. So in one bag, I have a 28F/-2C side, and a 48F/9C side. A **20 degree (F) difference in the two sides.** This should immediately sound great on those higher temperature nights I talked about above. This should immediately sound great to any PCT thru hiker wanting to know if they should get a 30F vs 20F quilt. Now, PCT hikers should absolutely get a 20F Simple Bag (can we please just call it a Simple Bag?) and they’ll effectively have a 20F and 40F bag all-in-one (depending on how the quilt maker designs the two sides.) I think continuous baffles are the way to go here. Despite my click bait title, not everything is perfect. AT thru hikers on a hot/humid night in Virginia? Yeh, you’ll probably want a traditional quilt. There are no absolutes here. You could pick a bag and add a little 20in zipper or go for a Enlightened Equipment Conundrum style. Although, it’s not like Simple Bags have ZERO venting. On a hot night at 8pm I would still lay there, let my core cool down, work the cooler side of the bag up to my knees, waist, chest and not cinching the neck line. Another con to simple bags, you will get some bellows action (hot air escaping) at the neckline. So be sure to get a neck baffle, but I consider that a must on any bag. Traditional quilts have plenty of this bellows action too through its openings. Lastly, you need to hit the mark on your body width. Do not under order the width or it will be too cramped.  TLDR: A Simple Bag (and no, this isn’t a traditional sleeping bag) keeps you warm by staying draft free and it has a warm side and a less warm side.  Ok. Thanks Attention: u/KatabaticGear u/EnlightenedEquipment u/Western_Mountaineeri 

There isn’t really an absolute best, but I like Katabatic for a quilt and western mountaineering or feathered friends for a bag. I prefer quilts down to around the low 20s, bags below that. Having a pocket in your quilt for a sleeping pad seems silly to me.

I tested the Timmermade Serpentes against the FF Tanager and found that the 20F Serpentes was both lighter (423g) and warmer than the Tanager (520g). The false bottom on the Serpentes also makes it much easier to dump heat than the Tanager. The theory behind continuous baffles sounds great but if you move a lot during the night you can forget about it; the down will migrate.

For sleeping bags I do Feathered Friends. PHENOMENAL products. Carefully selected down feathers and they don’t have to kill the animals to get them. I’ve got 3 different Feathered Friends sleeping bags for different temperatures, including an ultra thick one that I’ve used alone sleeping in no-tent self-dug snow trenches in the middle of Yellowstone in January. The outer layer of the sleeping bags is synthetic, but the primary ingredient is natural feathers. I also have one of their down packable jackets, but it’s too hot, even in -20F. Last time I camped in deep snow for a week, alone, on cross country skis, pulling all my gear on a Fairbanks siglin pulk sled behind me, I found I didn’t need much during the day, because I was working so hard I was always hot. At night I would dig a trench, lay a tarp across the top, supported by my ski poles, and sleep in my FF down bag on top of a thermarest. I’d keep my boots in the bottom of the sleeping bag so they didn’t freeze overnight. Wool socks, wool long underwear, wool sweater, synthetic wind-and-snow protecting pants and jacket. Wool hat, neck gaiter, and gloves. Synthetic outer-layer for gloves to keep my fingers drier. Smartwool makes merino wool boxer briefs. You need less than you think. (Except calories, holy f— do you need a lot of those.)

Well the Tanager is a FF bag too. Very similar, Vireo is just dual rated.

\+1 for Feathered Friends. Got one of theirs for our daughter to take to Pakistan

I have the Tanager. I love it. It is a very smart and simple design and makes a ton of sense to me. I usually have a hat on anyway. I am pretty short too… so I can snuggle down inside and it goes over my head. I do tend to get cold if temps are in the low 20s… but I run cold so I wear extra layers if I know the temps at night. I totally agree this is an overlooked option to save weight while providing warmth. I also have a Zpacks 30 degree quilt. I use both. This is great for when I know temps are in the low 40s or higher at night. I usually wear a sleep top and don’t even bother with strapping it to my pad since I use it more like blanket.

The FF tanager is more than double the price, probably only slightly warmer than the Neve Gear Waratah, which fixes all the quilt problems you mentioned anyway (doesn't let in drafts, doesn't add weight from reinforcements, doesn't have finicky quilt straps - i don't even use the straps on my Waratah until about -3C and Im a very restless sleeper) For only marginally heavier but way more comfortable and useful, I'll take the Waratah. The tanager doesn't even have a proper neck baffle. Its also 7D, so expect a short lifespan, vs the Waratah's 10D and full neck and foot baffle.