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Sea to Summit Ultra Sil Compression Sack


    Sea to Summit Ultra Sil Compression Sack

    Trim the weight—and the bulk—of your load with this incredibly light, tough compression sack from Sea To Summit. See details

    • $26.95 - $36.95

    Item # 766677

    Trim the weight—and the bulk—of your load with this incredibly light, tough compression sack from Sea To Summit.

    Product size and color

    Trim the weight—and the bulk—of your load with this incredibly light, tough compression sack from Sea To Summit.

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    Trim the weight—and the bulk—of your load with this incredibly light, tough compression sack from Sea To Summit.

    • Thirty-denier diamond ripstop Cordura® fabric is siliconized for water resistance and offers a smooth finish for easy packing
    • Four extra-long straps provide even compression and allow sack to be used to maximum capacity
    • Flip-top lid prevents tangled straps; pull handle on bottom aids in unpacking
    • Quality construction and durable, bar-tacked reinforced stress points hold up to years of heavy use


    Item 766677

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    View specs for sizes: 6 L, 10 L, 15 L, 20 L, 30 L

    Sea to Summit Ultra Sil Compression Sack Specs
    6 L10 L15 L20 L30 L
    Best use
    6 liter10 liter15 liter20 liter30 liter
    366 cubic inches610 cubic inches915 cubic inches1,220 cubic inches1,831 cubic inches
    Cordura nylonCordura nylonCordura nylonCordura nylonCordura nylon
    5.5x14 inches7x16 inches8x18 inches9x20 inches10.5x23 inches
    2.4 ounces2.6 ounces3.0 ounces3.3 ounces4.1 ounces
    Gear capacity (L)
    Gear capacity (cu. in.)
    Compression straps

    Sea to Summit Ultra Sil Compression Sack

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    Sea to Summit Ultra Sil Compression Sackis rated4.6out of5by10.
    Rated5out of5byfromuse them all the timeI'm writing this review because there have been some negative durability/construction reviews. I have two 30L compression sacks that I use for my synthetic sleeping bags – I put a 20-degree bag in one and a 40-degree bag + double liner in the other. I really have to mash the 20-degree bag into the sack, punch in the sides, and then compress it all the way down to the end of the straps, usually by kneeling/sitting on it, to get it into the dry bag I use in our portage pack - and I've done so easily 100 times. With such rough handling, I always expect something to pop, but so far, not a ripped seam, not a stitch broken – they're as good as new. I also have a 6L and a 10L that I use backpacking, but nothing has taken the abuse of the 30L sacks. One of these days, we'll get down sleeping bags and maybe I won't have to wrestle with them so much! I always try to pack them so that anything hard is packed in the middle of the sack so it won't poke the fabric when compressed. I've also found that compressing the sides part-way progressively around the sack keeps the load even and prevents the sack from becoming lopsided/lumpy. They are a bit pricey, but if you're looking for lightweight compression sacks, these are whisper-light and they've held up great.
    Date published: 2013-12-05
    Rated5out of5byfromPerfect size to pack into 22" carryonI had to pack a weeks-worth of underwear and socks into a 22" carryon. The "large" size I already had was too big, but the "small" size was perfect. Filled it, cranked it down, and it fit perfectly into the luggage. I used the large one to hold items like shirts, pants, and shorts. They make good laundry bags too while traveling! These sacks are durable and lightweight so you don't sacrifice much by bringing them along on trips. I just wish they were more squared off so they fit better into rolling luggage. Round objects leave small open spots - a waste of valuable packing space. Also, most clothing isn't very round so squares and rectangles would be a good line extension. If they made them, I'd buy them.
    Date published: 2013-10-30
    Rated5out of5byfromIt does what it is supposed to do!The stuff sack is easy to STUFF and compresses well....does what it is supposed to do!
    Date published: 2013-09-22
    Rated5out of5byfromLove itBeing able to compress my sleeping bag in the sack makes a big difference in how I am able to pack my backpack which in turn makes a difference in how comfortable my backpack is. I also like the fact that it gives my bag a little extra rain ( or raging river) protection. Not much is worse than a wet sleeping bag at night!
    Date published: 2013-09-12
    Rated4out of5byfromDoes the trick!Used this to compress my synthetic Marmot Trestles 15° into a 14L sack. Did the trick and definitely opened up some space in my pack. Considered getting a waterproof sack, but didn't anticipate encountering any wet conditions.
    Date published: 2013-09-11
    Rated5out of5byfromSquish that bagThis bag works great in compressing the sleeping bag to a small nugget that easily fits into my backpack. I have an extra long, extra wide down bag that barely fit into the sleeping bag compartment of my pack when in the standard stuff sack. This lets me put bag, inflatable pad and small pillow in the compartment with ease. Sack also easily accommodates a set of sleeping shorts and tee to keep handy. Have not had to test the water resistance yet but was a bonus feature for a down bag.
    Date published: 2013-08-11
    Rated3out of5byfromNot Very DurableI have the 20 liter size. I roll my Thermarest up very small, pack my 20 degree sleeping bag around and on top of it and compress the whole thing down. This way, sleeping bag and pad take up the same amount of room as just the bag did in its original stuff sack. I don't have to compress very tightly to do this but a seam ripped after around ten uses. I like the sac otherwise, as it is very light and water resistant; however, I think it is rather expensive considering its lack of durability. The sack is still useable even with the tear, albeit less water resistant, so I still use it. It is even possible that I might buy the same one again despite its faults. You would think a compression sack would be constructed with compression in mind. I would recommend this to a friend for "gentle" use.
    Date published: 2013-05-30
    Rated4out of5byfromIt's a compression sackIt's a compression sack, you probably know what you are looking for in one. This one fit my sleeping bag, so I like it.
    Date published: 2013-02-20

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