Interested in shedding some weight from your overnight kit? The Feathered Friends Hummingbird UL 30 is a great way to start. Weighing in at just 1 lb 5 oz, it's one of the lightest 3-season mummy bags out there. That's no trick either. It really is a 3-season bag and will keep you warm down to at least its 30°F temperature rating. Through some form of wizardry, it also attains this low weight while still including a sturdy full-length zipper that's immune to snagging. Combine this all together and there's no mystery why it took home our Top Pick Award for Light and Fast Adventures.
REASONS TO BUY
Super lightweight
Incredible loft
Snag-proof zipper
Cozy hood
REASONS TO AVOID
Uncomfortably narrow dimensions
Bare-bones design
Noisy fabric
Its Achilles' heel, however, is sub-par comfort. That's because it uses particularly narrow dimensions to trim the ounces. This isn't a problem if you don't mind being confined inside lofty down heaven. But if you hope to be able to stretch your legs, a more roomy model might be a better choice.
Product Renamed
When we tested this bag, Feathered Friends referred to it as the Merlin 30 UL but they have since renamed it the Hummingbird UL 30. The two bags are identical. We link to the Hummingbird 30 in this review.
Expensive, awkward hood, good but not great zipper
Really pricey, kind of bulky, awkward hood closure
Below average warmth-to-weight ratio, bulky packed size
Average materials, limited features, basic design
Bottom Line
Our favorite when ounces matter, this is a full-size mummy bag that's both warm and ultralight
The best ultra-premium bag that combines warmth, low weight, good packability, and luxurious comfort
Our favorite premium backpacking bag to keep us warm at night when the temperature drops
Premium down in an hourglass shape that offers the roomiest lower body dimensions
An exceptional deal for a capable and sturdy backpacking sleeping bag for those looking to get outside without breaking the bank
Rating Categories
Feathered Friends H...
Western Mountaineer...
Western Mountaineer...
NEMO Riff 30
Mountain Hardwear B...
Warmth(20%)
8.0
8.0
10.0
4.0
6.0
Weight(20%)
9.0
8.0
7.0
7.0
6.0
Comfort(20%)
7.0
9.0
7.0
9.0
6.0
Packed Size(15%)
8.0
8.0
6.0
8.0
8.0
Versatility(15%)
8.0
7.0
8.0
8.0
6.0
Features & Design(10%)
7.0
7.0
7.0
9.0
6.0
Specs
Feathered Friends H...
Western Mountaineer...
Western Mountaineer...
NEMO Riff 30
Mountain Hardwear B...
Insulation
950+ FP Down
850+ FP Down
850+ FP Down
800 FP Down
650 FP Down
Compressed Volume
7.3 liters
7.2 liters
8.7 liters
7.2 liters
7.5 liters
Measured Bag Weight (Size Long)
1.45 lbs.
1.62 lbs.
1.86 lbs.
1.91 lbs.
1.98 lbs.
Manufacturer Claimed Weight (Size Regular)
1.33 lbs.
1.50 lbs.
1.81 lbs.
1.80 lbs.
1.79 lbs.
Compression/Stuff Sack Weight
0.8 oz.
1.6 oz.
1.6 oz.
2.4 oz.
1.6 oz.
Hydrophobic Down
No
No
No
Yes
No
Manufacturer Temp Rating
30 F
30 F
20 F
30 F
30 F
EN Temp Rating (Lower Limit)
Not rated
Not rated
Not rated
29 F
30 F
Fill Weight
12 oz.
13 oz.
17 oz.
10.2 oz.
15 oz.
Compression or Stuff Sack Included
Stuff
Stuff
Stuff
Compression
Stuff
Shell material
Pertex Endurance (10D)
Extremelite (12D)
Extremelite (12D)
Ripstop nylon (20D)
20D Nylon Ripstop
DWR Treatment
Yes
No
No
Yes
Yes
Liner material
n/a
n/a
n/a
30D Nylon Taffeta w/ DWR
30D Plain weave nylon
Neck Baffle
No
No
Yes
Yes
No
Small Organization Pocket
No
No
No
Yes
Yes
Zipper
Full-length / Side
Full-length / Side
Full-length / Side
3/4-length / Side
3/4-length / Left Side
Shoulder Girth
58 in.
64 in.
59 in.
62 in.
62 in.
Hip Girth
52 in.
Not stated
Not stated
54 in.
53 in.
Foot Girth
38 in.
39 in.
38 in.
59 in.
Not stated
Show full specification detailsHide full specification details
Our Analysis and Test Results
The Hummingbird is almost magical for the warmth and comfort it provides in such a lightweight package. Although it ultimately missed out on the Editors' Choice Award, it still deservedly earns our Top Pick for Light and Fast Adventures. The competition was extremely close so it's vital to weigh the pros and cons of our top-rated bags to ensure you pick the perfect one for you.
Performance Comparison
Recording our thoughts during a field test with the Feathered Friends Hummingbird.
Credit: Jack Cramer
Warmth
The Hummingbird UL contains 12 ounces of ultra-premium, 950+ fill-power, goose down. Although this is a little less insulation than other primo bags with similar temperature ratings, it has a narrow fit that requires less material to provide the same amount of warmth.
Feather Friends does put their sleeping bags through formal EN temperature
testing. Instead they supply their own manufacturer rating for the Hummingingbird of 30°F. We felt it provided similar warmth compared to the average bag that receives an EN lower limit rating of 20°F. With this level of insulation, it's an excellent middle-of-the-road bag that's well-suited for all but the coldest or warmest 3-season uses.
The Hummingbird's 30F rating is generous compared to other bags. We think it's warm enough for cold spring and fall nights.
Credit: Jack Cramer
Weight
Weighing in on our scale at 1.45 pounds for a size long, the Hummingbird UL is truly ultralight. This is made all the more impressive when you consider its substantial insulation and sturdy, full-length zipper that provide significant warmth and versatility, respectively.
On paper, their are a few bags with reported weights and temperature ratings that would seem to offer even better warmth-to-weight ratios than the Hummingbird. Our testers, however, found many of the temperature ratings on these competing bags to be overly optimistic. The Hummingbird's insulation, in contrast, felt much warmer than its 30° rating. We, thus, consider this bag to be the top bag in warmth-to-weight ratio and have trouble attributing this outstanding performance to something other than sorcery.
Comfort
Our only significant complaint with this bag is its comfort. Don't get us wrong, the fabric is soft, and the incredible loft of its ultra-premium down creates an extremely cozy cocoon. Rather, our comfort complaint is due to its narrow fit.
With 58 inches of shoulder girth, the Hummingbird is one of the narrowest bags we tested. Virtually all of our testers are happy inside bags that are 64 inches wide, but as the girth shrinks complaints steadily rise. Our larger and side sleeping reviewers, in particular, said the Hummingbird felt constrictive. This probably isn't a problem for shorter trips, when the benefits of less weight can overshadow the drawbacks in comfort. However, for longer trips, or over the full lifetime of a bag, the review team felt that the average user would likely prefer a wider design.
For some sleeping styles, the comfort difference between a narrow bag like the Feathered Friends Hummingbird (orange) and a wider bag can be substantial.
Credit: Jack Cramer
A smaller complaint about the Hummingbird's comfort related to the nosiness of its Pertex Endurance shell fabric. When manipulated, this fabric creates a distinct crinkling sound. Although it's only subtly louder than most other bags, some lighter sleepers felt the difference was enough to disturb their sleep.
Packed Size
Like its low weight would suggest, this bag packs down pretty small. With the help of an aftermarket compression sack, it achieved an impressive 7.3 liters in compressed volume. This is slightly larger than some bags with less insulation, but nearly identical to any other bag offering a similar level of warmth.
The simple drawstring stuff sack this bag comes with is ultralight, at just 0.8 oz, but not super effective at compression. To fully enjoy the Hummingbird's small packed size you will need to get a third-party compression sack. This will set you back an extra twenty bucks but will shrink its packed size by roughly 20%.
The Hummingbird is pretty bulky packed inside the yellow stuff sack that it comes with. A good compression sack, however, can compress it considerably smaller.
Credit: Jack Cramer
Versatility
The Feather Friends bags we tested feature some of the longest zippers in the backpacking sleeping review. These allow the Hummingbird to vent excess heat as well as any other bag we tried, expanding the range of temperatures it can comfortably be used in. When opened fully, the long zipper also effectively turns the bag into a quilt for sharing on a chilly morning or between climbing partners during a "light and fast" bivouac.
Its one versatility drawback is its down insulation. Like all down products, this down will lose its ability to insulate if it gets wet. Thus, this bag is not well-suited for particularly wet climates or activities.
Continuous horizontal baffles allow you to move feathers to the top or underside of a bag to adjust the amount of insulation.
Credit: Jack Cramer
Features and Design
Although it's just a simple mummy bag, we like this bag's features and design. The zipper, as we mentioned above, is super long for venting excess heat.
It also incorporates an effective anti-snag zipper slide. The fabric adjacent to this zipper is stiffened by an internal strip of flexible plastic that further reduces the likelihood that fabric will get caught in the zipper's teeth.
The Feathered Friends bags that we tried feature a Y-shaped zipper slide and an internal strip of flexible plastic to prevent the zipper from snagging.
Credit: Jack Cramer
We also prefer the hood design on this and other Feathered Friends bags compared to some of their closest rivals. Placing the hood's drawstring slightly back from the hood opening creates a cozy tube of insulation around the face that our testers found to be warmer and more comfortable.
The snap that seals the Hummingbird may be simple but it's easy to snap and effective at keeping it closed.
Credit: Jack Cramer
Value
Although the Hummingbird certainly isn't cheap, it does cost a little less than similarly performing bags. If you're going to spend several hundred dollars on an ultra-premium sleeping bag, however, this meager savings probably isn't worth factoring into your decision. Instead, simply choose the ultra-premium bag that's best suited for your sleeping style and expected applications. Whether that's the Hummingbird or one of its competitors, you will receive an expensive bag that still provides an exceptional value because it can last for over a decade.
The Hummingbird is our favorite backpacking sleeping bag for when we want to go light. Pair it with a backpacking tarp to really trim the weight of your overnight kit.
Credit: Jack Cramer
Conclusion
The Feathered Friend Hummingbird's greatest strength is its incredible warmth-to-weight ratio. We also think the long, anti-snag, zipper performs better than any other, giving this bag an edge in convenience and versatility. However, the narrow dimensions that contribute to this bag's low weight come with drawbacks for its comfort. Larger and side-sleeping testers found these dimensions to be uncomfortably constrictive. The Hummingbird is thus our Top Pick for users interested in "fast and light" missions where sacrificing some comfort for lower weight is often worth it. The average backpacker, however, may prefer a slightly heavier bag with more roomy dimensions.
GearLab is founded on the principle of honest, objective, reviews. Our experts test thousands of products each year using thoughtful test plans that bring out key performance differences between competing products. And, to assure complete independence, we buy all the products we test ourselves. No cherry-picked units sent by manufacturers. No sponsored content. No ads. Just real, honest, side-by-side testing and comparison.