Western Mountaineering UltraLite 20 Degree Sleeping Bag: Great Quality for a Steep Cost

Sleeping bags are an investment. Most hikers and campers want a sleeping bag that is warm, comfortable, water-resistant, and preferably lightweight. Most importantly, they need to be durable.

No one wants to invest in a sleeping bag that will need to be replaced within a few years, especially if they are paying top dollar for a sleeping bag that supposedly has an excellent reputation.

For individuals looking to invest in a simple sleeping bag that can keep them warm and comfortable during the night, the Western Mountaineering UltraLite 20 Degree Sleeping Bag is an option worth considering.

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Product Specifications

  • Interlocking draft tubes and a full down collar that wraps snugly around your neck to help seal in heat
  • Breathable, water resistant shell protects you (and the down) from condensation
  • 5 1/4″ spacing of continuous baffles that encircle the bag from zipper to zipper
  • 16 oz of 850 fill is highly compressible, light weight and toasty warm
  • 5″ of loft, rated at 20ºF

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There aren’t a lot of bells and whistles to the Western Mountaineering UltraLite Sleeping Bag. However, the simplicity of this sleeping bag is what makes it unique.

There doesn’t need to be an overwhelming number of features included with a sleeping bag to make it worth purchasing. Simplicity can be a blessing in disguise.

For example, this sleeping bag is easy to roll up and put back into its stuff sack when you’re done using it.

Unlike some other stuff sacks, there are no buckles or straps that help compress the bag into a smaller shape. Despite the lack of straps, this sleeping still compresses to become smaller than one square foot and it weighs no more than 2 pounds.

Therefore, this sleeping bag is an extremely lightweight and compact 4-season, mummy-style sleeping bag. Furthermore, this sleeping bag does not sacrifice warmth for weight.

There is 16 ounces of goose down put into this sleeping bag, as well as baffles, draft tubes, a full down collar, and a full-length zipper that prevents heat from escaping throughout the night.

Therefore, individuals won’t have a problem staying warm when snuggled into it. The Western Mountaineering Sleeping Bag has a great reputation for being durable; so it should be a great companion for many years.

Best Use: When and Where To Sleep

Using your sleeping bag properly is key to making it last for years. However, using it properly is also key to enjoying your camping or hiking trip.

Using a sleeping bag designed for summer during the winter, and vice versa, will make sleeping at night miserable. Therefore, knowing when your sleeping bag will be the best use to you is essential.

Fortunately, the Western Mountaineering Sleeping Bag is a 4-season sleeping bag and is a great option for individuals who love to backpack. This sleeping will keep you warm in temperatures as low as 20°F.

It’s a popular option for individuals planning to hike in the ALP or along the Appalachian Trail. Therefore, this sleeping bag is versatile, allowing you to bring it along on many different types of hiking and camping trips.


Even though the Western Mountaineering UltraLite Sleeping Bag is available in three different sizes, and a total of five different variations, each bag compresses down to the same size when packed into the stuff sack.

When packed away, this sleeping bag is only 7 x 13 inches. Therefore, it can fit into backpacks of varying sizes without taking up too much space.

Packing this sleeping bag away is easy. You might have to flatten the loft down a bit, but there shouldn’t be much of a fight to roll up the sleeping bag and slip it into the stuff sack. Unlike some other stuff sacks there are no cinch straps or buckles that help compress the sack into a smaller shape.

However, the lack of straps shouldn’t be a problem. This sleeping bag does come with a larger, additional storage sack, which prevents it from being compressed when it isn’t being used. Storing the sleeping bag in a roomier sack will help prevent the loft from deteriorating.

Design And Durability

The design of the Western Mountaineering Sleeping Bag is simple. It looks like any other mummy sleeping: wide near the shoulders and narrow near the feet. The unique part about this sleeping bag is the zipper.

Individuals can choose to have their full-length YKK zipper sewed onto the right or the left side of the bag. While this may not be a life-or-death feature, it’s a unique customizable feature that other sleeping bags don’t have.

To keep individuals warm, the Western Mountaineering Bag contains 5 inches of 850 goose down throughout the entire sleeping bag.

Furthermore, the bag contains interlocking draft tubes, baffles, and a full down collar that prevents chilly air from finding its way into the bag. This sleeping bag is also designed to be slightly narrower than other mummy sleeping bags to prevent pockets of dead air from forming.

However, don’t let the simplicity of this bag fool you. This sleeping bag has a reputation for being durable. The material used for it is called ExtremeLit, which is a unique mixture of fabric and yarn designed by Western Mountaineering.

The yarn is 12 denier and contains 420 threads per square inch. Therefore, this bag shouldn’t come apart at the seams or tear unexpectedly.

When cared for improperly, or handled too roughly, this bag could deteriorate more quickly than other sleeping bags, due to the lightness of the material. There have also been a few reports claiming that campers shouldn’t place this bag directly on the ground.

However, most individuals that have used this sleeping bag have found it to be comfortable, lightweight, and durable.


Going on a hiking, camping, or backpacking trip, means packing quite a bit of equipment. Unfortunately, the more equipment you pack the heavier your backpack gets. Having a heavy backpack can make hiking difficult and unenjoyable.

Therefore, the key to packing supplies for a long trip is to find equipment that is both light and durable. Fortunately, the search for a light 4-season sleeping bag is over.

Unlike many 4-season sleeping bags, the Western Mountaineering UltraLite Sleeping Bag is extremely light. Most 4-season “ultralight” sleeping bags weight about 4 pounds. However, the smallest size of the Western Mountaineering Bag only weighs 15 ounces and the largest size only weighs 17 ounces.

Therefore, this sleeping bag is correctly advertised as “ultralight.” You never have to worry about this piece of camping equipment weighing you down during your daily hikes.


Getting a restful night’s sleep plays a significant role in being able to hike long distances each day. There are a few ingredients that are needed for sleeping soundly during the night. One of those ingredients is warmth.

It’s difficult to sleep when you are shivering due to the cold. Therefore, it is important to find a sleeping bag that will keep you warm during the entire night.

Fortunately, the Western Mountaineering Sleeping Bag has a 20° Fahrenheit rating. While it’s not the warmest 4-season sleeping bag, as some 4-season sleeping bags can handle climates that drop into the negatives, this sleeping bag’s 20°F rating will still allow you to sleep in places that can get chilly during the night.

For example, many individuals have used this sleeping bag while climbing and hiking the Alps.

While this sleeping bag advertises a 20°F rating, some individuals have reported using this sleeping bag in temperatures as low as 8°F while hiking the Appalachian Trail. Therefore, this sleeping bag can keep individuals warm in a variety of chilly climates.

However, using this sleeping bag in climates lower than 20°F is not recommended. While it may keep you from freezing in extremely chilly weather, it most likely will not keep you comfortably warm.


Having enough room to move your limbs while snuggled into a sleeping bag is a key component to sleeping comfortably.

While a sleeping bag should feel slightly snug, no one wants to feel as if they can’t move at all after settling down in their sleeping bag. Therefore, taller individuals often search for sleeping bags available in a larger size.

The Western Mountaineering Sleeping Bag is available in three sizes; although, there are a total of five different variations.

The three sizes include: 5’6,” 6,’ and 6’6.” Individuals who are exactly 5’6” should purchase the 6’ sleeping bag, and individuals who are exactly 6’ should purchase the 6’6” sleeping bag. Otherwise, there won’t be extra room length-wise and the bag will feel tight and small.

The availability of three sizes allows individuals to purchase a sleeping bag they know they can comfortably fit into length-wise. However, this sleeping bag is designed to have a narrower girth than other sleeping bags.

The width dimensions are as follows: shoulders 59 inches, hip 52 inches, and feet 38 inches. Despite being designed to have a narrower girth, this sleeping bag still has a reputation for feeling spacious.


Having a comfortable sleeping bag is just as important as having a warm sleeping bag. Being cold can make it difficult to sleep during the night, but feeling every pebble on the ground can also make it difficult to get a good night’s sleep.

While many hikers bring along a sleeping pad, hikers that don’t use sleeping pad need a sleeping bag that will protect them from the hard ground.

While the Western Mountaineering Sleeping doesn’t have any specific features designed to make it comfortable, individuals have found it to be extremely comfortable to sleep in.

This sleeping bag does have 5 inches of loft, which not only keeps individuals warm but also makes it more comfortable to sleep on the ground.

Furthermore, the ability to purchase a sleeping bag with the zipper on the left or right side adds to the comfortability of the bag.

While it doesn’t make it more comfortable to sleep on the ground, being able to choose which side the zipper is on adds to the convenience of the bag. Being able to easily zip the bag up makes it easier to settle down and get comfortable.


Having a water-resistant sleeping bag is very important for several reasons. Tents can leak and produce condensation. Therefore, water can find its way into your tent and when that happens you’ll be relying on your sleeping bag to stay dry.

Furthermore, a sleeping bag with down needs to be water resistant to protect the down from becoming wet and smelly.

Fortunately, the shell of the Western Mountaineering Sleeping Bag is both breathable and water resistant.

Therefore, when condensation forms inside the tent, or water manages to leak inside the tent, you shouldn’t have any problems staying dry. The water-resistant shell should also protect the down, prevent it from becoming damaged or deteriorating quickly.

Value For Money And Guarantee

Overall, the Western Mountaineering UltraLite Sleeping Bag is a great option to consider purchasing. It has a very simple design, which isn’t a terrible thing. There aren’t unnecessary zippers or buckles to mess with and it’s easy to pack into the stuff sack.

It is lightweight and doesn’t take up much space, which is nice when you have to bring along a lot of other equipment.

Furthermore, this sleeping bag is warm. Some sleeping bags sacrifice warmth for weight, but that isn’t the case with the Western Mountaineering Sleeping Bag. It is rated for temperatures 20°F and above.

However, it has been known to keep individuals from freezing in temperatures as low as 8°F. Therefore, this sleeping bag can be used year-round, making it a long-term investment.

While this sleeping bag is durable and loved by everyone that uses it, the price is quite steep. While this is a reliable sleeping bag, you might be paying for the name rather than the quality of the bag.

There are other sleeping bags with same quality and customer ratings as this sleeping bag, but cost much less. However, some individuals prefer paying more for a sleeping bag manufacturer that is well known. If you are willing to pay top dollar for a sleeping bag then this sleeping won’t disappoint you.

Close Competitors: Similar Products You Might Like

The steep cost of the Western Mountaineering UltraLite Sleeping Bag might have you debating whether it’s the right sleeping bag for you, despite its excellent qualities.

However, before you decide whether this is the right sleeping bag for you or not, take the time to look at these similar products.

Comparing sleeping bags is a great way to determine which sleeping bag will fit your needs, as well as your budget.

Western Mountaineering Versatile Sleeping Bag

The Western Mountaineering Versalite Sleeping Bag is similar to its counterpart. It has the same simplistic design that the UltraLite Sleeping Bag has. However, it does have a few differences. For example, it contains 6” of loft instead of 5,” which allows it to handle slightly colder temperatures.

It can keep individuals comfortably warm in temperatures as low as 10° Fahrenheit. Therefore, it can handle colder climates a little better than the UltraLite Sleeping Bag, but not by much.

Unlike its counterpart, the Mummy Sleeping Bag only comes in two sizes: 6’ and 6’6.” However, individuals can still choose which size they would like the zipper to be on. Even though there are only two sizes, individuals of all varying heights should be able to pick the size that is best for their body size.

The weight of this sleeping bag is only a few ounces heavier than the UltraLite Sleeping Bag.

The reputation of the Versatile Mummy Sleeping is excellent. Similar to its counterpart, this sleeping bag has a reputation for being warm, comfortable, and durable. However, it is more expensive than the UltraLite Sleeping Bag.

Considering there isn’t much a difference between the two bags, the UltraLite Sleeping Bag might be the better choice, unless that 10-degree difference matters to you.

Sea to Summit Spark SP III Sleeping Bag

The Sea to Summit Spark SP III Sleeping Bag is designed similarly to the Western Mountaineering UltraLite Sleeping Bag. It comes with a stuff sack, laundry bag, and storage bag.

The stuff sack is slight different, as it contains two straps that help compress the sleeping bag. However, this sleeping bag is slightly heavier than 2 pounds, but not by much.

Like the UltraLite Sleeping Bag, this sleeping bag contains goose down and uses baffles to keep individuals warms in temperatures around 20°F. It is only available in two sizes and the zipper is on the left side of the sleeping bag.

Made from ripstop nylon, with a water-resistant seal on the sleeping bag’s shell, this sleeping bag is quite durable. Unless cared for improperly, this sleeping bag should not tear easily.

Pricewise, it is about the same as the UltraLite Sleeping Bag. Overall, there isn’t much difference between the two sleeping bags. The UltraLite Sleeping Bag is slightly better at handling colder temperatures, is slightly lighter, and slightly smaller than the Sea To Summit Sleeping Bag.


Except for its price, the Western Mountaineering UltraLite Sleeping Bag probably meets every requirement on your check list. It may not have a fancy design, but it in this case simple is better.

It is easy to roll up, pack into the stuff sack, and compress without the need for cinch straps and buckles. Therefore, it doesn’t take much effort to fit this sleeping bag into backpacks of varying sizes.

This sleeping bag is one of the lightest 4-season sleeping bags on the market. Most 4-season sleeping bags weight around 4 pounds, but the largest size of this sleeping bag only weighs 17 ounces. Having a lightweight sleeping is nice when you have to lug around a large amount of hiking and camping supplies.

Furthermore, this sleeping bag doesn’t sacrifice warmth and comfort for weight. Therefore, you should have no problem sleeping during the night. To help you decide whether the Western Mountaineering UltraLite Sleeping Bag is the right one for you, here is a comprehensive list of the pros and cons.


  • 4-season Sleeping Bag
  • 5” of Goose Down
  • Comfortable
  • Lightweight
  • Compact


  • Pricey
  • Narrow

Overall, this is a great sleeping bag to consider investing in. While it may be one of the cheaper sleeping bags in this article, it is one of the more expensive 4-season sleeping bags on the market. However, if you can get past the price tag, then this sleeping bag won’t disappoint you.

There are no negative reports about this sleeping bag, which is rare. This sleeping bag is warm, comfortable, water resistant, and durable. When cared for properly, this sleeping bag will last for years.

Western Mountaineering UltraLite 20 Degree Sleeping Bag
  • Packaging
  • Design And Durability
  • Weight
  • Warmth
  • Dimensions
  • Comfortability
  • Water-resistant
  • Value For Money And Guarantee


For those who don’t mind paying top dollar for their camping equipment, then the Western Mountaineering UltraLite20 Degree Sleeping Bag is the sleeping bag to invest in. This sleeping bag provides maximum warmth and comfort throughout the night. Containing 5” of goose down, individuals won’t find it difficult to say warm in chillier climates. This sleeping bag is a sound investment, as it can be used in a wide range of places, such as in the Alps or on the Appalachian Trail. There isn’t anything fancy about this sleeping bag, but sometimes simpler is better. Not only is this sleeping bag easy to put away, it is light and compact. Therefore, individuals can fit it into smaller backpacks and won’t have to worry about lugging around an unnecessarily heavy sleeping bag.

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2 thoughts on “Western Mountaineering UltraLite 20 Degree Sleeping Bag: Great Quality for a Steep Cost”

  1. Sea to Summit Spark SP III Sleeping Bag really looks great so I will surely check it out. I have been looking for a nice and affordable bag which I will give to my girlfriend and I think this is it. The price is reasonable given the fact that it has many great reviews.


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