Sea to Summit Ultra-Sil Compression Sack
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Sea to Summit Ultra-Sil Compression Sack

Sea to Summit Ultra-Sil Compression Sack is rated 4.8 out of 5 by 31.
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4.8 Star Rating
From $20.21   $42.95
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Product Description Item No.   10046648

The Sea to Summit Ultra-Sil Compression Sacks. When you need to compress your gear without adding weight Ultra-Sil Compression Sacks are the perfect choice.

FEATURES of the Sea to Summit Ultra-Sil Compression Sack

  • 4 straps for even compression
  • Extra long straps so these sacks can really be filled to capacity
  • Bar tack reinforced stress points
  • Pull handle on the bottom
  • Slippery finish for easy packing

- + Product Specifications
Dimensions (Extra Small): 6 x 14 in.
Dimensions (Small): 7 x 16 in.
Weight (Extra Large): 3.8 oz
Weight (Extra Small): 2 oz
Weight (Large): 3.3 oz
Weight (Medium): 2.7 oz
Weight (Small): 2.3 oz
Dimensions (Medium): 8 x 18 in.
Dimensions (Extra Large): 10.5 x 23 in.
Dimensions (Large): 9 x 20 in.
Features: Compression Straps
Best Use: Camping, Mountaineering and Alpine, Backpacking
Stuff Sack Closure: Drawcord
Rated 3 out of 5 by from Weight Savings Not Worth the Lack of Durability I recently replaced some ancient heavy compression sacks with these. I got an XS for my down jacket, and a M for my 25 degree Western Mountaineering Bag. The M lasted only about 15 days (in decently rough desert conditions). The ultrasil has good tear strength, but it's weakness is anything pointy! By the end of that 2 weeks, there were at least 5 decent small holes in it, the tiny cord lock and one buckle broke. It doesn't seem up to the task of being a sleeping bag compression sack. However, I still use the XS with my down jacket, as I compress it, and keep it in a light drybag with other clothes. These work great for that, but seem to be lacking when used in rougher conditions.
Date published: 2011-01-18
Rated 5 out of 5 by from Light and Organized Compression sacks are compression sacks, they squish stuff and that's it, right? Well, kind of. As far as squishing stuff goes all of my compression sacks do a good job. The differentiating factor is how much of a tangled mess they become when not in use. This is where the Ultra-Sil shines. The lid is attached to the sack and while that doesn't sound like a big deal it makes the sack the easiest to use of all the compression sacks I have used. As far as compression sacks go it's a game changer.
Date published: 2015-05-02
Rated 4 out of 5 by from it squishes stuff I does exactly what the name says it compresses things. A little on the expensive side but I love the quality of Sea to Summit stuff. Mine was actually black so it matches my ninja outfit when I stuff it inside it to squish it down to a more packable size.,,4 straps also helps keep things balanced evenly during compression. I will keep getting this type and brand of sack when I need different sizes of compression sacks. A ninja has a lot of gear he needs to compress sometimes.
Date published: 2009-12-14
Rated 5 out of 5 by from Functional and durable I took this on a two-week camping trip in Africa. I stubbornly decided I would do the entire trip with a 33L backpack - tent and all! I stuffed my Big Agnes Fly Creek 2-person tent, my Mountain Hardwear Ultralamina sleeping bag, and my pack towel in this thing and crammed it into the bottom of my bag. For the record, that's roughly 10 pounds of crap in a 5 pound bag. Basically, I abused it like a red headed step child every day for two weeks. Just get it - a solid stuff sack is a traveler's best friend.
Date published: 2011-10-16
Rated 5 out of 5 by from Lightweight! Love the ultra-sil nylon I bought this wanting the XXS small size and settled for the XS size; which I'm glad that I did! The XXS would have been too small for what I wanted. The XS size fits my Marmot Nanowave55 PERFECT! I wanted a lighter compression sack than the one that came with the sleeping bag and decided on this. I have multiple Sea to Summit stuff and/or compression sacks and would highly recommend and Sea to Summit products to anyone. Quality product that last and serve their purpose well!
Date published: 2015-11-02
Rated 5 out of 5 by from Flap Jacks Anyone? I am a touring bicycle enthusiast. This is piece of equipment is no longer and option but a must! The build is fantastic, great double stitching and very durable. The bag medium compression sack holds 5 days of clothing (shirts, shorts, socks, and boxers), a rain jacket and jeans and compresses them down to the size of a stack of pancakes. The icing on the cake is the weight, the fact you only add a few ozs to the overall pack weight is amazing. I now own one in every size!
Date published: 2016-01-04
Rated 4 out of 5 by from Great Sack with One Complaint This is the 3rd Sea to Summit Ultra-Sil Compression Sack I've purchased and for the most part I've been very happy with them. They're much more durable than I would expect for being made out of such a lightweight fabric. The one complaint I have is that the webbing is so slippery that it sometimes folds over in the ladder lock, and can even cause the ladder lock to rotate. I haven't found this to negatively effect the performance of the bag, it can just be annoying to fix.
Date published: 2015-10-05
Rated 5 out of 5 by from Ultralight and ultraresistant When I saw the compressiong sack I thought "Such a garbage bag!"...but it's the best compression sack I've ever had! I use a Small size for keep my Down Jacket during my travels, and it fits pretty well. I was able to compressed the jacket to 1/3 of the original size. Cordura material and reinforced stress points are great. The four straps works incredibly well, and the Flip-Top-Lid design is a great idea.
Date published: 2010-10-31
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I see you have answered the sizes' capacities in liters, but could you give us the dimensions (in inches) of each size as well?

Asked by: msteppe91
Hey there, Thanks for reaching out to us! As requested, here are the dimensions, in inches... 3XS- 4 in X 9 in 2XS- 5 in X 10 in XS- 6 in x 14 in S- 7 in x 16 in M- 8 in x 18 in L- 9 in x 20 in XL- 10.5 in x 23 in I hope this helped you out!
Answered by: Rocko Gigsby
Date published: 2015-12-31

What are the maximum capacities, in liters, of each size?

Asked by: nace
Hey Nace, Here are the capacities in liters for each size: 3XS- 1-2.5 L 2XS- 1.3- 3.3 L XS- 2-6 L S- 3.3-10 L M- 4.5-14 L L- 6.5-20 L XL- 10-30 L
Answered by: Rocko Gigsby
Date published: 2015-10-27

What size of Sea to Summit sil nylon eVent sack do I need for a sleeping bag that rolls to 9" X 12"?

Asked by: Bwana
Hey there, Thanks for the question. With those dimensions, the closest fit you could get would be the size Large, which is 9" x 20", however that might be too long for your bag. Unfortunately all smaller sizes of this are too narrow in the width to fit your bag. Once this is compressed down using the straps the height of the sac might not matter, but if you're looking for an extremely compact compression you may have to try another compression sac with different dimensions.
Answered by: Rocko Gigsby
Date published: 2016-07-03
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