Kelty Cosmic Synthetic 0

Running these analyses costs money. Buy through my links to help keep lights on! I may get a small commission.

Overall

#611 in

Outdoor Sleeping Bags

according to Reddit Icon Reddit

Sentiment score25% positive
1
1
2
Last updated: May 13, 2026

Reddit Reviews

Reddit IconDestructablePinata
6 months ago

Sitting pad: Get a CCF pad and cut it to size if you're short. That gives you a sleeping pad and sitting pad. Light and packable sleeping bags are expensive. You'll have to do some research on this. The most suitable I've found on Amazon is the Kelty Cosmic Synthetic 0 for my uses, but it's not very packable or light. Naturehike makes decent tents. There are a lot of good sun hoodies out there. I would recommend just going by both the product and seller reviews. Socks: I prefer Smartwool over all other brands. I prefer the way they do their cushioning, and they fit me very, very well. I've also had better luck with them than Darn Tough. Darn Tough does have a lifetime warranty, but I feel weird about sending in used socks, hence I never utilized that warranty. Switching to Smartwool has been a godsend. Other items: Compass of quality, such as the Cammenga 3H or Suunto MC-2. Rite in the Rain. Pace count beads. Multi-tool. Sewing kit with good thread. Gear repair items, like Gear Aid patches or Aquaseal SR. A stash of snacks and electrolytes. Outdoor Research Ferrosi Hoodie.

Reddit IconLetMany4907
7 months ago

For casual three-season camping around 0°C, synthetic’s way easier on the wallet. Marmot Trestles or Kelty Cosmic Down alternative bags hold up fine, and you don’t freak out about melting water or sweat ruining insulation.

Reddit IconHelpful_Affect_7958
7 months ago

My Kelty 0 bag, so I can wear shorts and t shirt and still be comfortable

Reddit Iconajhejunk
Reddit Iconcwcoleman
5 months ago

Can you add more specific details? You have this labeled as 'travel' - but ask about camping gear. I assume you are asking about the 'wilderness' type of backpacking - right? What is the low temps you plan to sleep in? You say no snow - but 'colder temps' - a number would help. What is your budget? Do you have $500 to spend? $5000? You say 'wreck bank account - but everyone's bank account is different size. How old are you? Man or Woman? (many packs and sleeping bags are gendered) Do you already have a good sleeping pad? This is also critical to a good / warm night sleep. Do you already have a tent? Sure - Kelty is a find budget getting started brand. They make an okay Cosmic down sleeping bag that's popular for wilderness backpacking. I wouldn't go for their backpacks really. Here are some default recommendations from Amazon: * [https://www.amazon.com/Kelty-Sleeping-Backpacking-Recycled-PFAS-free/dp/B0CSPFW5Q1](https://www.amazon.com/Kelty-Sleeping-Backpacking-Recycled-PFAS-free/dp/B0CSPFW5Q1) * [https://www.amazon.com/Osprey-Atmos-Backpacking-Backpack-X-Large/dp/B09JXQDZG5](https://www.amazon.com/Osprey-Atmos-Backpacking-Backpack-X-Large/dp/B09JXQDZG5) * [https://www.amazon.com/Therm-Rest-Original-Ultralight-Camping/dp/B00453NA1E](https://www.amazon.com/Therm-Rest-Original-Ultralight-Camping/dp/B00453NA1E) * [https://www.amazon.com/Therm-Rest-Ultralight-Backpacking-Sleeping/dp/B0CS4NHPVP](https://www.amazon.com/Therm-Rest-Ultralight-Backpacking-Sleeping/dp/B0CS4NHPVP)

Reddit Icongmxrhythm
12 months ago

Then I'd say the new REI Radiant 20. It's a mostly down bag, but with synthetic in the footbox to accommodate sweat and if it gets wet in the night from rain (because most people stretch out and end up putting their feet against the tent wall which might have condensed). The Kelty Cosmic is a close second.

Reddit IconInternConnect6963
9 months ago

Kelly cosmic down bags are amazing bang for buck. REI has generous return policies as well, so if you get into a bag you don’t like, you have the option to return it for a year. More expensive bags/huge discounts don’t necessarily mean they are going to fit your needs. I currently sleep in the Big Agnes Lost Ranger, which is a 3in1 sleep setup. It is a quilt and a sleeping bag, which means you can sleep with just the quilt, just the bag, or if it’s cold enough you can nest the sleeping bag inside the quilt. It’s on the more expensive side, but it could be beneficial looking into a similar setup. I would however recommend investing in a nice sleeping pad that has a decent R value. I currently sleep on the Big Agnes Rapide SL Insulated (regular) and I LOVE IT. it comes in all different types of widths and lengths. I’ve slept on it for 2+ weeks in the Yosemite side country and I’ve never had a single issue with it. long story short, i’m a huge fan of the Kelty Cosmic Down line. there are also a few REI branded bags that may be worth looking at.

Reddit IconStapledOK
9 months ago

Can def get closer to 2 for a little more money. Kelty cosmic or REI brand stuff on sale. Down is much lighter than synthetic. Quilts are also an option...

Rankings by Use Case

Top recommendations from others in the same boat

Other Reddit Recommendations: