Zpacks Zip Around Sleeping Bag Review | 20F Tested

Are you looking to shave weight from your pack without sacrificing comfort? That was our goal with this Zpacks Zip Around Sleeping Bag review. The design of this new Zpacks Zip Around Sleeping Bag is one that lends itself to comfort rather than Zpacks’ typical air at being the most ultralight gear on the market, but they still managed to keep this firmly in the ultralight category.

Zpacks was founded in 2004 and quickly made a name for themselves in the ultralight world. I had the opportunity to test out the Zpacks 20-Degree Zip Around Sleeping Bag, and it is built to impress! I’d classify this bag as somewhat of a hybrid between a traditional sleeping bag and a modern quilt. Needless to say, I was stoked at the idea of lightening my pack by almost two pounds with this Zpacks Zip Around Sleeping Bag and still having something super comfortable to sleep in. Let’s dive into the details.

Zpacks Zip Around Sleeping Bag review - Zpacks sleeping bag review

Opening day of the 2022 Colorado archery season, I found myself and a couple of my buddies six miles from the trailhead and within 150 yards of a huge herd of elk, including multiple bugling bulls. Exactly what I had been dreaming about since the end of the 2021 season! With no realistic way to close the distance in wide open terrain above timberline, we opted to play it safe thinking we’d have the remote basin to ourselves. We had hauled in fives day’s worth of food and gear to just under 12,000 feet in elevation and planned to try to wait out the elk for a better opportunity expecting them to be in early season “predictable” patterns.

Zpacks Zip Around Sleeping Bag review - Zpacks sleeping bag review

As the day moved along, the elk eluded us, but I began to ponder the potential reality of “what if” one of us had tagged out opening morning. We had spent nearly five hours hiking into this area, losing an arrow, and breaking two trekking poles along the way. My pack was pushing 50 pounds and we were suffering through 2000+ feet of elevation gain, hiking through tons of dead fall. Every imaginable snag had me contemplating any and every possible way to lighten up my pack for multi-day backpacking trips.

Zpacks Zip Around Sleeping Bag Specs:

I opted to go with the 20-degree broad/long version with the intent of using it as my primary bag for summer backpacking and scouting trips as well as in September during archery season when temperatures are usually reasonably warm. The long version of this bag fits a person up to 6’6” in height and weighs in at an insane 23.9 oz. The “Zip Around” feature offers a two-way, full length zipper with a draft tube and zipper guard to keep those pesky drafts out. Vertical baffles help ensure the down is not migrating to the sides of the bag, and I have had absolutely no issues with cold spots in my testing.

Zpacks Zip Around Sleeping Bag (20F Long/Broad)
Total Weight (with stuff sack) 23.9oz
Stuff sack (DCF) Included - 0.9oz
Footbox Rectangular
Girth 60 inches
Hood No
Material (shell and inner) .51 oz/sqyd Ventum Ripstop Nylon
Down Fill 900 FP RDS Certified Goose Down
WordPress Data Table Plugin

Several years ago, I bought some “ultralight” backpacking gear from a well-known name brand in the industry. My “3-person” tent weighed in at 56 oz. and my “0 degree” bag weighed 51 oz. For several years, this setup was my go-to for September archery as the tent was comfortable for two people and the bag kept me warm to around 25°F – 30°F.

Make sure to check out our other gear reviews and the Backwoods Pursuit YouTube Channel to help you decide what gear will help you stay out in the field longer!

I hadn’t spent much time testing other options and just assumed that 100+ ounces is what was required for a double-walled shelter and a comfortable down sleeping bag. It is rare in backcountry hunting to be able to literally cut POUNDS at a time out of your pack without making major sacrifices to comfort and quality. Enter Zpacks.

Sizing: Zpacks Zip Around Sleeping Bag Review:

Zpacks zip around sleeping bag review

Zpacks offers three different sizing options – short, medium, and long. They also offer a “standard” and “broad” girth to fit the user’s needs. The lengths are sized to fit 5’6”, 6’0”, and 6’6” respectively. Zpacks also has a handy sizing chart to ensure you get the right bag that fits your body type. The length and girth options are an example of Zpacks’ ingenuity in helping backpackers shave weight by tailoring the bag to their individual size.

I found the sizing to be true to form as I am 6’4”, 220 pounds, and the long/broad option fits me well with a bit of room to spare. In fact, I even found that on the colder nights, I could nearly fully tuck my head inside the bag with the extra length it has. Not for everyone I’m sure, but it was nice to be able to maximize the warmth. The Zpacks’ cut definitely has a slightly more “snug” feel to it than previous bags I have used. Not overly restrictive, but certainly tighter to the body than what I was used to.

Looking for a different sleeping bag? Check out our other sleeping bag reviews and ultralight quilt reviews!

Having only previously used bags with a hood, I wasn’t quite sure what to think of the hoodless design. It took a bit of getting used to, but I actually didn’t mind NOT having the hood. I tend to be an active sleeper and occasionally did have my pillow sneak off while tossing and turning on my Exped Ultra 3R pad. The solution I found that worked best was to stash a few of my extra layers and gear around the top of my Zpacks Triplex Tent (review coming in fall of 2023) and the Sea to Summit Aeros Pillow.

Zpacks zip around sleeping bag review

Once I did this, my pillow no longer fell off. Before using this Zpacks sleeping bag, I typically would stuff my pillow inside my hood so it would move with me throughout the night. One minor adjustment I plan to make before my next outing is to add in the “pillow locking” options that Sea to Summit and others offer to avoid having a runaway pillow at night.

Weight: Zpacks 20F Zip Around Sleeping Bag Review

The weight of this bag is where Zpacks truly shines in my opinion. With the 20-degree long/broad bag weighing in at 23.9 oz, you’ll be hard pressed to find a lighter sleeping bag of this quality. The 10-degree standard girth option (24.6 oz for the short bag, 26 oz for the medium, and 27.6 oz for the long) and 30-degree bag (15.7 oz for the short bag, 16.6 oz for the medium, and 17.5 oz for the long) are also right there on the front lines of defining the never-ending pursuit of “ultralight.”

Zpacks zip around sleeping bag review

My immediate impression when I unboxed my new bag was “no way.” It was hard for me to fathom how small this bag compresses down. The “roll top” stuff sack is included and adds 0.9 oz to the total weight. I was curious to see if the advertised weights were correct, so I weighed the bag and the stuff sack on two different scales with each coming in at 24.4 oz, or a difference 0.4 oz below the total advertised weight. The added space in my pack paired with the reduction in weight is a significant benefit I’m looking forward to on my upcoming backcountry outings.

Warmth: Zpacks 20F Zip Around Sleeping Bag Review

As I mentioned, my older “ultralight” zero-degree bag usually kept me warm to around 25 degrees at best and weighs in at 51 oz. I was skeptical of the Zpacks 20-degree Zip Around Sleeping Bag and its temperature rating purely due to the fact that it is 26+oz lighter than the “zero degree” bag I was used to. In testing this bag on chilly Colorado nights, I slept in my First Lite base layer and early season pants (prAna Stretch Zion) as I typically did with my older “zero degree” bag to ensure a fair comparison.

Zpacks zip around sleeping bag review

I found that I started to notice the slightest chill when temps dipped to around 35 degrees. Not enough to disrupt sleep, but enough to make me zip up all the way to the top and tighten the draw string. Full disclosure – I tend to sleep cold and wasn’t terribly surprised that I wasn’t comfortable down to the suggested 20-degree rating. For me, it would absolutely be feasible to run this bag into the mid to upper 20s by adding another couple of layers while sleeping on my Exped Ultra 3R Pad.

To confirm the lower limit of my comfort with this bag, I switched over to my late season Exped Downmat with a 7.1 R value on another outing. It did help a bit with extending the bag’s lower limit, but again, I found I started to feel slightly chilled through the bag at around 30 degrees while just wearing my base layers. After adding on the First Lite Origin Hoody, I was much more comfortable.

Regardless, I was very impressed with the capability of this bag, and the warmth/weight ratio blows my older sleeping bag out of the water. There is always a bit of a variance person to person and company to company with comfort ratings on sleeping bags, but I was pleasantly surprised it performed so well.

My recommendation with any sleeping bag is to purchase one with a rating 10-15 degrees below any
expected temperature to avoid tossing and turning on cold nights. It is easy to vent and cool off, but not
as easy to warm up once you’re chilled.

Versatility: Zpacks Zip Around Sleeping Bag Review

Zpacks zip around sleeping bag review

The Zpacks 20-Degree Zip Around Sleeping Bag does not have a hood which did take a bit of getting used to for me. Again, this is another value add with the weight savings and the hood not really offering much for warmth. I usually sleep with a hooded layer or keep a jacket nearby to keep my head warm and found I didn’t even notice the hood not being there after a few nights out. One alternative option would be to add on the Zpacks Goose Hood. This hood weighs in at a microscopic 0.59 oz and can easily replace the warmth of a traditional hood in your sleeping bag.

Zpacks zip around sleeping bag review

With the full zip around option, the Zpacks 20-Degree Zip Around Sleeping Bag can easily become a blanket or quilt on those warmer summer nights when you aren’t worried about getting cold. Alternatively, you can partially open the two-way zipper to vent as needed.

Drawstring: Zpacks Zip Around Sleeping Bag Review

Zpacks zip around sleeping bag review

The elastic drawstring cord can be modified as needed from cinched tight up around the neck, to loose as shown in the pictures to allow for better airflow. For colder nights, I found the drawstring was super easy to operate and didn’t slip as I tossed and turned. With temps in the low 20s, I could quickly tell if I had any wasted space up around the drawstring. With the hood-less design of this bag, the drawstring becomes much more critical for heat retention when compared to the traditional hooded bags I have used in the past. I love the versatility of the drawstring to stay comfortable with changing temperatures.

Down/Materials: Zpacks Zip Around Sleeping Bag Review

The Zpacks 20F Zip Around Sleeping Bag is constructed with 900 fill, treated goose down. Zpacks uses responsibly sourced and certified “DownTek” goose down. The loft of this bag is truly impressive. It has the look of my Sea to Summit Alpine 5-Degree Cold Weather Bag I use on late season hunts. I measured the loft at around 7-8” (total). Comparing it to my “zero degree” bag, it sits about a full 2 inches higher side by side. Add in the fact that Downtek includes a “C0” water repellent that allows it to stay dry 90% longer than an untreated bag. 900 fill treated goose down is truly incredible.

Zpacks zip around sleeping bag review

The inner and outer shell of the bag is made from Ventum Ripstop Nylon. This high-quality, denier fabric weighs in at 0.51oz per square yard. It is also “DWR” treated to handle light moisture, although it is not truly waterproof. In my experience breathing on the bag during cold nights, I did get some light dew and frost on the top of the bag close to my mouth, but did not have any issues with it soaking through the outer layer of the fabric. The fabric is extremely soft to the touch and does not feel quite as course as some of the other bags I’ve tested.

Footbox: Zpacks 20F Zip Around Sleeping Bag Review

Zpacks zip around sleeping bag review - Zpacks sleeping bag review

One of the unique features of Zpacks is the tapered footbox with horizontal baffles. I wear a size 14 shoe and was curious to see if my feet would feel like they were saran wrapped. The foot box is definitely a bit more snug than a traditional style bag, but plenty big enough to not restrict movement and it did not bother me at all. Additionally, not having extra space to try to keep warm helps maximize efficiency of the bag. The two-way zippers allow for the foot box to be opened up to air out your feet if needed.  

Because of my size, I use a wide/long pad to be able to not have shoulders slipping off the edge of the pad when laying on my back. I found that the tapered footbox actually was helpful to keep more sleeping bag on the pad as I moved around at night.

What I Liked: Zpacks 20F Zip Around Sleeping Bag Review

Zpacks zip around sleeping bag review


There is so much to like about the Zpacks 20F Zip Around Sleeping Bag. For me the biggest game changer with this bag is the weight savings. While the price tag is steep ($519.00 retail for the broad/long), it is money well spent to shave significant weight from my pack.


The versatility this bag provides is also notable to accommodate a wide variety of temperatures. I’m a big fan of backcountry gear that can serve multiple purposes. I use the stuff sack to store my food in and hang from a tree while I’m out for the day and overnight to avoid issues with predators. It is durable, waterproof, and easily stays shut with the combination of a Velcro/snap buckle with rope tied around it and hoisted up and down. Again, anything in my pack that serves multiple functions is a value add for me!

What I Didn’t Like: Zpacks 20F Zip Around Sleeping Bag Review


While it may be a personal preference, I wish this Zpacks bag had sleeve or pocket of some sort inside the bag to stash my phone in while sleeping. I’ve tested a few other bags that have incorporated this concept into their design to avoid having to search for your phone or a headlamp overnight. While this is a very minor inconvenience, a sleeve or pocket is an added feature that adds minimal weight and something I’d love to see Zpacks add in the future.


Zpacks zip around sleeping bag review

It seems to be common in all of my sleeping bags, but I did have a few times where I managed to snag the fabric in the zipper. I found that slow and steady wins the race. As long as I didn’t rush, properly aligned the draft tube and tucked it in, the zipper guard worked perfectly well and prevented accidentally locking up the zipper.

Conclusion: Zpacks Zip Around Sleeping Bag Review

Overall, I was thoroughly impressed with the Zpacks 20F Zip Around Bag. Its versatility, weight to warmth ratio, and quality materials make it an obvious standout in the ultralight category!

Don’t feel like this specific bag is for you? Zpacks has a wide range of sleeping bag and quilt offerings worth checking out. Zpacks also has a 2-year warranty covering any defects in material or workmanship. I haven’t needed to use the warranty yet, but it is always nice when a company stands behind their products.

I’m already looking forward to having this bag in my pack come September. Hopefully, that trip will entail packing meat in addition to this high quality, ultralight bag!

Buy Zpacks Zip Around Sleeping Bag

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