Fun lightweight sleeping bag, good value
929009
The color and design are fun.  It is very lightweight so good for sleepovers and summer camping.  Seems roomy enough for an adult and still functional for a child. zipper moves easily, there were some threads hanging along seams and zipper when first opened. It is very difficult to get the sleeping bag back into the carry bag it came with and there are no other ties or restraints for it. Over all its a decent bag.
902862
I bought this bag last week and used it on a tent camping overnight. It got down to 38 degrees F and very windy and I was warm and comfy. I used a 35 degree F rectangle (not mummy) Coleman bag last year in the same conditions and was awake shivering all night. I am a 5'7" female and although the bag is long (6'2" or 6'3") my feet didn't get cold at all. I was also super warm in my chest and torso area, which can get cold for women in a men's bag. The extra "collar" around the shoulder area with cinch was a huge plus. It kept the cold air out. The stuff sack isn't the most compact, but it's not enormous, and the bad stuffed back in no problem. This bag is a great value for the price. Perfect for parents of a Cub Scout who are going to go on a few overnights a year.
3367407
My 9 year old son loved it. Probably too small for him to sleep in but makes a nice little fort or private hide a way, plus there's no bottom so it works best on a rug. A little confusing at first to set up as the instructions are a bit vague, but actually very simple once you figure it out (polls will bend) and those L shaped tools that look like allen head wrenches are actually stakes which you probably won't be using unless you're setting the tent up outside. Nice sleeping bag (for the price) maybe a little thin to take camping in cold weather.
4180906
Great, thin, small sleeping bag.  Not the most comfortable, but does the job well!
4569587
I've now got two of these.

They're weird. They barely fit me (6', 185-195lbs), but I still love them.

Their outside is slippery as all get out, and they're definitely about 5c plus 'optimistic' on their temperature rating. In my case, they fit more like a mummy bag than a sleeping bag.

They're good for warm weather camping, but I love them as supplemental, more or less disposable, blankets. If you completely unzip them, let them puff up, and aren't relying on them as your sole sleeping bag, they rule. Lightweight, tiny, easy to stuff, they're surprisingly warm when used as blankets. They'd also make decent bag liners if you needed more warmth from a more substantial bag. Think of this as a versatile, medium weight throw fleece that can double as a sleeping bag in a pinch during summer, and you'll probably like them.
Only caution is they're made of very thin material, and it can catch on the zipper, so move slowly and carefully when zipping to keep from catching.
2961449
Very good sleeping bag for its price range.  The nylon fabric is soft enough for comfort, and the bag is warm enough for use down into the 30s F, possibly colder.  The zipper slides smoothly so that the bag is easy to exit quickly.  A bit heavy and bulky for pure backpacking use, but just right for vehicle-supported camping.
2361898
The sleeping back is lightweight and plenty warm enough for camping in fall weather when nights are cool (but still above freezing).  It rolls up and fits easily back into it's cover.
1062953
Used Cosmic 21 sleeping bag on a multi day camping trip in temperatures in the upper 20's.  I was very satisfied with the warmth of the bag.  Only con is the stuff bag that comes with this sleeping bag is a bit small and not very water resistant.  I purchased a separate Kelty compression sack. and the bag compressed very well.  Overall very satisfied with the value and would purchase again.
1343859
I bought this sleeping bag for a late October camping trip. I needed a bag that was fairly compact and pretty warm but i wasn't looking to break the bank on a $300 The North Face bag so i decided on this. When it arrived i was pleased to see that it fit snugly into the sleeping  bag compartment of my backpack. I took it out of the pouch and noticed how soft the inner lining was which was good for comfort. The bag seemed to be overall well made and comfortable. I did have some doubts as to how warm the bag would be in below freezing temperatures as sleeping bag seemed sort of thin. When it came time for the field test however I can certainly say that I did not get cold. The first night of camping the temperature dropped to 29 degrees F, and i stayed fairly warm. I would recommend a good sleeping pad to pair this with though!

Overall for the price I think this is an excellent bag especially compared to some that are exponentially more expensive. It will definitely keep you warm, it is definitely compact, and lightweight to boot! Definitely a great buy!
2137340
I really like this sleeping bag! I am about 6 feet tall and weigh 175 pounds and I fit perfectly in this bag, which is nice because that does not always happen. I've taken it camping to the beach and mountains and it has kept me at a nice, cool temperature all night. I like the hood, as it keeps my ears warm at night. I strongly recommend this budget sleeping bag for anyone who's interested!
1311009
This is a very lightweight summer-season, warm weather bag. It's all synthetic, so it won't trap humidity and will dry quickly. It packs compactly into its very lightweight drawstring bag (included).
The colors on mine are exactly like the Amazon photo-- royal blue and a dark charcoal gray synthetic interior. The same smooth fabric is used inside and outside the bag. The insulation is a very light single layer of polyester. Holding the bag up to sunlight, I can see through both layers and the insulation. It's that lightweight.
The Amazon photo suggests this has a thick fluffy loft, perhaps 3" thick or more. In reality, this is actually fairly thin, perhaps 5/8" to 3/4" at the thickest point. The amount of insulation, and overall warmth, is about the same as a traditional lightly insulated sports warm-up or "dugout bench" windbreaker jacket.

The zippers are not YKK but they seem to function fine. The bag unzips out completely into a flat rectangle, so this could double as a very light 'throw' blanket in a hammock or as a stadium blanket.
The attached hood is a plus. There's a small velcro strap at the top of the zipper intended to prevent it unzapping itself as you move during the night. Right hand zip. All polyester.
Currently this is offered in only one size. I'm 6'0 and 185 lbs, and I fit into this just fine. My feet do reach all the way down to the bottom zipper, but I fit. Someone taller-- 6'2, or taller-- might not find this to be long enough.

It's washable, and most marks will just brush off or sponge off. Nice beach blanket, and it's easy to shake the sand off at the end of a day at the beach.

Now, about the stated temp rating of 30-40 degrees F. That may be a typo error. Realistically this very lightweight bag is a nice, affordably priced choice for an indoors sleepover party at a heated house, or any indoors location that's heated to at least 60-65 degrees F. I think that's its best use.
If you've seen those one-layer medium weight fleece sleeping bags intended for kids' indoor sleepovers and slumber parties, this bag will be almost exactly that warm, and maybe 3'-5' more.
As an outdoors bag, well, I'm a lifelong camper, I've used many bags and I own a number of serious cold weather bags, and I think most people will become chilly, and then downright cold, in any temperatures below 60', and definitely below 50'. This is not a bag for 40', and certainly not 30', even in a tent and on a good pad. I hope the seller will correct the temp rating numbers in future to a more realistic 50-60 rating (in my opinion).

And for indoors sleepovers in a warm house, this is a cool and inexpensive little bag. Or in a warm, humid climate where nights are 60 or so, this will be a good choice. This could also be doubled up with a silk or polyester liner sheet, or the fleece bag I mentioned, and then you start extending the temp's that this would be comfortable in.

Sample sent for testing and independent review. I like this, it will be my beach throw and summer bag in the Southeast, and great for reading in a hammock in spring and fall.
I hope this review has been helpful as you comparison shop. Happy trails, everybody.
2313462
This is a great sleeping bag.  Lots of wiggle room :)
116968
This is a great sleeping bag if you don't mind the size and weight of it when it's packed up.

My husband and I fit comfortably in it with room to toss and turn.  My son had room to slide in too for story time or morning cuddles.

I haven't tested it in really cold weather, so I can't attest to that point, but overall it was really soft and comfy and we love it!
2206285
A good kid sleeping bag for using indoors or on a hot summer night outside. The stuffing in this bag isn't very thick so I would not use in cool places or on camping trips where temperatures get low. There is no temp rating on the bag, so you'll have to decide for yourself. Overall its a fun sleeping bag for sleepovers.
574277
this is a nice all around sleeping bag.  It does seem a little more narrow than my other mummy bags, so this may be one that I use more than my hubby does.  Zippers all function smoothly.  The hooded portion ties off fairly well.  Nice economy bag.  My husband has VERY wide shoulders and isn't sure he would be comfortable in this, but for 90 percent of the population it would be fine.  :)  I would definitely say this would be a good all around sleeping bag, it will be put to the test camping in a few weeks when deer season starts.

Rolled up this is nice and compact, offering ample warmth in a small amount of backpack space.
4228664
This sleeping bag is very well made and is very comfortable.  It is a good thickness to keep you warm but also lightweight so it's not heavy to carry. I like the thickness of the pillow it makes for a better nights sleep.
1778847
These have replaced sleeping bags for our couple's camping. I bought two, and together with a double pad, and a car-stored wool blanket for very cold nights, have comfortably slept in the chilly New England autumn where temps drop to the 20s. We stayed warm and are far more comfortable than we ever were in separate bags, or bags zipped together (which is never as roomy as you think).

They pack small enough, and unless you're going for week-long trip, could even be used for backpacking. For us, they're perfect for our canoeing expeditions, as they're lightweight and take up little space in the dry bags. Most of all, they're warm, and give us a bit more comfort and room. Makes me question how sleeping bags ever became so standard, when only apparently necessary in the most fitting and unusual conditions.

A great purchase.