Nemo Siren Down Sleeping Bag: Staying Warm with Affordability

Nemo Siren Down Sleeping Bag
Daniel Carraway
Written by Daniel Carraway

The Nemo Siren Down sleeping bag is one of the cheaper down sleeping bags that you could pick up. This sleeping bag is designed to give you a lightweight and easy to carry cover for those colder winter nights on your backpacking trips. Since the winter is excruciating in some of the most beautiful places, you will need to invest in a good sleeping bag that will ensure that you stay warm throughout the trip.

Product Specifications

  • One of the lightest quilt-style sleeping bags on the market constructed using the highest end fabrics and 850FP down
  • Side tie loops, drawstring opening, and collar snap keep you tucked in and minimize drafts on cold nights
  • Insert your pad inside Siren or snuggle on top
  • 850 fill power down clusters trap layers of air for natural insulation while high loft ensures warmth and compressibility

Check the price on Amazon

If you love backpacking, or even camping in those cold and strenuous conditions, you will need to have a decent sleeping bag that is capable of resisting the temperatures and ensuring that you can stay warm. While there are also multiple synthetic sleeping bags that you could choose from, we have found that down and especially those made by NEMO, is capable of standing the test of those tough winters.

We have decided to look a little deeper at the NEMO Siren Sleeping Bag and find out exactly what sets this sleeping bag apart from the rest and why it should be a good investment for those who love camping or backpacking in the winter or near the poles.

Nemo Siren Down Sleeping Bag review

In this article, you should learn exactly why these sleeping bags are so good and also see the amount of effort that the NEMO Company has invested in bringing you a top quality sleeping bag. That being said, here is our review of the NEMO Siren Sleeping Bag.


In this review, you will learn why and how this sleeping bag will be ideal for those who consider themselves to be minimalist campers of backpackers. We have looked deeply at every aspect and due to the impressive design, this sleeping bag was chosen. Outdoor hobbyists should really continue and see how this sleeping bag is designed and how impressive it can be for your next outdoor adventure.


The size of the sleeping bag when it is folded will be fundamentally important. If you are an avid backpacker, you will need to have a super minimalist approach and this could potentially lead to some people looking for different sleeping bags. The NEMO Siren is one of those lightweight sleeping bags that should easily find a home inside your backpack.

The overall size of the sleeping bag when folded will be the size of around 2 water bottles or a 5-litre can. This could seem a little too large for some people, but we do believe that it should be able to squeeze and fit in the backpack quite easily and smoothly. The sleeping bag only weighs around 19 ounces and this should definitely be light enough for you to easily carry it along with you.

Compared to the same size synthetic sleeping bag, this NEMO Siren will be much lighter and with the down in the sleeping bag, you should not have any troubles molding and shaping the carry bag to get it inside or in between some of the other things in your backpack.

Design and Durability

The design and the durability should also be carefully looked at. Nothing can be as frustrating as having your sleeping bag tear or give in when you are camping or backpacking in extremely cold conditions.

This NEMO sleeping bag is quite durable and it has been designed with 10D ripstop nylon materials. This nylon shell has also been treated with DWR and this will ensure that water cannot penetrate and damage the sleeping bag.

Nemo Siren Down Sleeping Bag design

The inner lining has been constructed from 10D mini ripstop nylon and this will also give you decent durability and ensure that you need to worry about those smaller and minor tears that could happen on the inside. The length of the sleeping bag is around 6 feet and anyone with this length should be able to comfortably fit inside.

The shoulder and hip girth are quite wide, but the smaller knee girth is traditional that you will find in the mummy designs. This sleeping bag has shoulder girth of around 53 inches and that should be enough for those who feel like they are a little too big for the sleeping bag.

When looking at the design a little closer, you will find that this sleeping bag works best with a sleeping pad. The sleeping pad will work in conjunction with the bag and you will be elevated off the ground to have a decent sleeping experience.

It is also worth mentioning that this sleeping bag does not come with zippers. This could make it harder to get inside, but you will not have a zipper area for the cold to peer through.

Nemo Siren Down Sleeping Bag insulation

We also like the fact that this sleeping bag has been constructed with clusters. These clusters are included to keep the down spread evenly and this will be perfect if you are a crazy or rough sleeper. No cold spots should emerge. This will also keep the breeze from ever getting inside and you will most likely have a great night time experience on your backpacking trips.

Finally, we should look at the foot box. The foot box on this sleeping is quite narrow and you will not have a lot of space to move your feet in. The foot box will also keep the sleeping pad secure and you need not worry about the sleeping pad moving around when you are sleeping. NEMO also designs great sleeping pads that should be compatible with this sleeping bag.


The insulation of the sleeping bag is also really important and you should ensure that you are fully insulated in the coldest areas of the world. The sleeping bag features a down fill power of 850. This is immensely high and should keep the heat inside your sleeping bag. The fill weight is around 10 ounces, this is not extremely heavy, but if you are camping in areas with temperatures of around 30 degrees Fahrenheit, this sleeping bag will definitely keep you warm.

Nemo Siren Down Sleeping Bag

The clusters that we mentioned in the design will be one of the main ways that you stay insulated. The down will not be shifting and moving around, which should keep you from having those cold spots where the wind can come in. The added DWR will also keep the down from falling flat when it comes in contact with water or ice, which is common in the Great White North.


Getting inside your sleeping bag and taking long to warm up will definitely not be ideal and you will need to have a sleeping bag that could potentially keep you warm and get you to that level of warmth very quickly. If the sleeping bag can keep you warm, you should not have any troubles with cold feet or hands and you will also have a fun sleeping experience.

The NEMO Siren is designed for temperatures of around 30 degrees Fahrenheit. This is not very cold but should be ideal if you plan on backpacking in temperatures just above freezing. Backpacking the mountains will not be ideal and you will not be able to stay warm in those extreme temperatures unless you do add a comforter to improve the heat retention. The sleeping pad will also be imperative to keep the cold from getting up through the ground.

This sleeping bag will give you great multifunctional use. You will easily be able to give it to a friend who might unexpectedly be sleeping over at your house. When traveling in your car, the sleeping bag can be used if you need to pull off the road and get some rest before continuing on your journey. In the coldest of city temperatures, you should have no troubles with this sleeping bag, it is also recommended that you do try and stay close to warmer areas when camping with the sleeping bag in the winter.

While the sleeping bag is designed for close to freezing temperatures, we would recommend that you do consider adding a good comforter to ensure that the sleeping bag does not have to be the only thing that keeps you from getting cold. The sleeping pad will also be extremely imperative.


We all want to be comfortable and have a comfortable sleeping experience when camping or backpacking. If you cannot have this comfortable experience, you will not be able to enjoy the journey during the day. If you decide to use the sleeping bag without a sleeping pad, you will be exposed to the little bit of loft that is offered by the only 10 ounces of down filling. The sleeping pad will be handy and keep you elevated off the ground and allow you to enjoy the sleeping experience much more.

Nemo Siren Down Sleeping Bag with pad

We have already mentioned that the sizing might be a little small in certain areas. The shoulder girth should be fine and you should not have any troubles when you need to turn. If you are a larger individual, the sleeping bag might seem a little narrow and your feet will definitely feel like they are a little bit cluttered and smothered. The cluster design will form some sort of comfort and protection and this could potentially lead to a better sleeping experience.

We would like to mention this again, but the sleeping pad must be included if you plan on having a great experience. This elevation could make a huge difference and keep you warm, insulated and also very comfortable on your backpacking experience. You should just find the best lightweight sleeping pad that could fit in your NEMO Siren sleeping bag.

Unique features

Much like with any good sleeping bag, this sleeping bag also comes with its set of special and unique features. The NEMO Siren sleeping bag has a few features that do set it apart from the competition and will certainly make it a better sleeping bag. This sleeping bag might not be ideal for every opportunity, but if you buy it for the right opportunity, it will certainly keep you happy.

  • Extremely lightweight: The NEMO Siren sleeping bag is designed to be very lightweight. It can easily be carried along in a backpack and then taken out to be used. This lightweight feature will certainly make life so much easier for you. The sleeping bag can also easily be compressed and this will all be thanks to the down filling.
  • Decent durability: The 10D nylon with ripstop is designed to resist tears on the ground and when you might snag something. The down has also been compartmentalized in clusters and these clusters will ensure that you need not worry about losing all of the down if the sleeping bag does take some damage.
  • No zipper feature: The sleeping bag does not have any zippers and this is usually great of you are planning to go to colder conditions. The zipper area will not be available for the cold to get in and the drawstrings could let you dictate how tight you want the sleeping bag to be clinging.
  • Designed with space for a sleeping pad: The sleeping pad is very good to have when you are planning to go out camping or backpacking. The sleeping pad can easily be fitted into this sleeping pad and this will give you much more comfort and keep the cold from getting in through the bottom. This sleeping pad sleeve will not let the sleeping pad move and it should stay in place without any hassles.

Value for Money and Guarantee

Depending on where you plan to go traveling, the NEMO Siren should be a great sleeping bag that could meet your needs and keep you warm. The sleeping bag is not that expensive and many can see it as a great budget option for camping or backpacking in the early or late winter months.

The sleeping bag offers great value and there should be no problems in terms of durability and comfort. The colder arctic weather might not be ideal for you to take this sleeping bag and climbing mountains will definitely not keep you impervious to the elements.

There are, however, a few different sleeping bags that will keep you warmer and might even be a little more durable. The only negative thing is that you will have to pay a little more expensive price for these better sleeping bags. But, the world has shown that you will usually get what you pay for. Unfortunately, the sleeping bag does not come with any specific guarantee and you will need to keep it from getting damaged.

Main Competitors

Marmot Hydrogen Sleeping BagMarmot Hydrogen Sleeping Bag

The Marmot Hydrogen Sleeping Bag is a great alternative to the NEMO Siren.

This sleeping bag contains a down fill power of 800 and this should be enough to keep you warm.

The mummy design is also perfect for ensuring that you have heat retention and the smoothly curved balls will ensure that the down does not easily move downwards.

The anatomically designed foot box will increase the warmth and should make the sleeping bag retain heat a little better.

The only thing that might not be as comfortable on this sleeping bag is the fact that the zipper is sometimes in the way and might snag the sides when opening and closing.

Western Mountaineering Megalite Sleeping BagWestern Mountaineering Megalite Sleeping Bag

The Megalite Mummy Sleeping Bag is one of the top sleeping bags that you could find.

This sleeping bag is a little more expensive than the NEMO Siren, but it also contains a little more down.

This extra down will give you that added fluffiness and also keep the sleeping bag lofted.

The sleeping bag is also stylishly designed and will easily fit into your backpack due to the lightweight construction.

We would highly recommend this sleeping bag if you are willing to dole out the extra cash for a little more down.

Nemo Argali Down Sleeping BagNemo Argali Down Sleeping Bag

The Nemo Argali Down Sleeping Bag is a mixture of synthetic materials and down. The synthetic materials will add to the overall durability of the sleeping bag and the 650 down fill power should be enough to keep you insulated. The design also features baffles that will keep the down from moving around and creating cold spots.

The NEMO Siren is a little better and it is also more affordable. It is a little heavier, but they added down should make it perfect for keeping you warm. This sleeping bag will be great for those who love camping and we still highly recommend it.


The NEMO Siren sleeping bag will be a great sleeping bag that you can choose for the close to 0-degree temperatures. This sleeping bag is really lightweight and will not take up much space in the backpack when it has been compressed. The decent down fill power will give you optimal insulation and the DWR treated nylon will keep the water from having an effect on the sleeping bag.

We love the fact that the sleeping bag does not have any zippers and this means that there should not be anything that could snag the materials. The added clusters or baffles should also keep the sleeping bag from making any possible cold spots and you can be assured that you will get a good rest every evening.

We highly recommend this sleeping bag for the affordable price and we believe that it will be best-suited for the avid backpackers. Campers will also enjoy the comfort, but if you are going camping, you will have the opportunity to look for something bigger and heavier. One of the main selling points is the fact that the sleeping pad sleeve has already been built in and this should give you optimal sleeping comfort.


  • Decent durability
  • Great compression capabilities
  • Lightweight and easy to fold
  • No cold spots will emerge
  • No zippers to snag anything
  • Includes a sleeping pad sleeve
  • Reasonably priced


  • Narrow design
  • Not the best for extreme temperatures

If camping or backpacking in the local routes near you is in the cards, the NEMO Siren sleeping bag should be a great option and you should consider picking it up. The sleeping bag is also really affordable and if you are looking for a very stylish and high-quality sleeping bag to buy for your children, this sleeping bag should be the one that you are looking at.

Nemo Siren Down Sleeping Bag
  • Packaging
  • Design and Durability
  • Insulation
  • Warmth
  • Comfort
  • Unique features
  • Value for Money and Guarantee


The NEMO Siren Down sleeping bag is one of the most affordable high-quality down sleeping bags that you could choose. This sleeping bag will be easy for you to carry along and the decent down fill power should keep you insulated in the colder areas. We would highly recommend that you do choose this sleeping bag to go camping in areas with not too cold temperatures and also consider adding a decent sleeping pad. The price tag is certainly impressive and the overall warmth will be ideal for those excruciatingly cold areas.

User Review
0 (0 votes)
Nemo Siren Down Sleeping Bag: Staying Warm with AffordabilityPlease let us know in the comment section below if you have had any experiences using this sleeping bag and also tell us if you think that this sleeping will be ideal for you. We would also like you to let us know what you think of the main competitors we have chosen and if you do think we might have missed any of your favorites.


Daniel Carraway

Daniel Carraway

Daniel Carraway joined our team last year. He is a gear freak when it comes to hiking, climbing and camping. He went to REI Outdoor School to meet new people and learn best practices. Don’t even try to argue with him about the latest backpack or ice axe, he tried most of them. Daniel’s dream is to climb Mount Everest.