Sea to Summit Ultra-Sil Day Pack Review
Compare prices at 2 resellers Pros: Insanely light, packs up super tiny, fits slightly larger people
Cons: Nearly no features, only one big pocket, super thin fabric, can feel contents
Manufacturer: Sea to Summit
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Sea to Summit Ultra-Sil Day Pack
|Price||$39.95 at REI|
Compare at 2 sellers
|Check Price at REI|
Compare at 3 sellers
$79.95 at REI
$34.95 at Amazon
Check Price at REI
|Pros||Insanely light, packs up super tiny, fits slightly larger people||Great features and pockets, easy to use, adjustable torso length||Great access to your gear, big pockets, simple yet versatile||Shockingly lightweight, padded shoulder straps, useful features, packs into own pocket||Lightweight, useful features, flap to cover cinch top, inexpensive|
|Cons||Nearly no features, only one big pocket, super thin fabric, can feel contents||Water bottle pockets are a bit small, front stow pocket is a bit small||Unsupportive hip belt, not the most breathable back panel||No hip belt, small overall size, no back padding - can feel contents||Small fit, hip belt not load-bearing|
|Bottom Line||A bare-bones ultralight pack for those really dedicated to cutting out ounces||This pack can comfortably do-it-all with excellent features, strong durability, and impressive adjustability||A durable, versatile pack that's both easy to use and easy on your wallet||An ultralight solution that doesn't cut out all the comfort and features||A good, grab-and-go bag for smaller users, but not ideal for long hikes or heavy loads|
|Rating Categories||Sea to Summit Ultra...||Osprey Tempest 20||REI Co-op Trail 25...||Osprey Ultralight S...||REI Co-op Flash 18...|
|Ease of Use (25%)|
|Specs||Sea to Summit Ultra...||Osprey Tempest 20||REI Co-op Trail 25...||Osprey Ultralight S...||REI Co-op Flash 18...|
|Measured Weight||3 oz.||31 oz.||30 oz.||4 oz.||10 oz.|
|Back Construction||Lightweight nylon||AirScape backpanel; large spaced horizontal padding bars covered by large-holed mesh||HDPE framesheet||Lightweight nylon||Lightly padded back panel|
|Hydration||None||External hydration sleeve||Inner hydration sleeve||None||Internal hydration sleeve|
|Hipbelt||No||Yes||Yes, removable||No||Yes, removable|
|Outside Carry Options||Short daisy chain||Lidlock helmet attachment, trekking pole quick-stow, large stretch front pocket, ice tool loop with bungee tie-off, side pockets, hip belt pockets, sunglasses shoulder stow, bike light loop||Pole fasteners, side mesh pockets with elastic enclosure||Side pocket||Various small loops, one tool loop (need bungee or webbing to secure poles to daisy chain)|
|Materials||30D ripstop nylon||70D x 100D nylon body, accent and bottom 420HD nylon packcloth||Recycled nylon||40D Nylon ripstop||Recycled nylon|
|Notable Features||Packs into its own pocket, carabiner included||Helmet attachment, trekking pole quick-stow, sunglasses quick-stow, bike light loop, shoulder strap pocket, stowable ice axe loops||Ability to add REI Trail 2 Waistpack for more storage, contoured foam harness, raincover included, bottom is reinforced to be abraison resistant||Packs into its own pocket||Removable back padding, cinch closure cover, removable sternum strap, converts into a stuff sack|
Our Analysis and Test Results
The Sea to Summit Ultra-Sil is the smallest, lightest daypack we reviewed. Sea to Summit used 30-Denier ripstop nylon and cut out all padding to make this pack weigh just 2.7 ounces.
For a pack that has literally no padding anywhere, this pack is… well, not comfortable unless you pack it right. It has no hip belt or load lifters or sternum strap, and the shoulder straps are padding-less. They do, however, have a very flat, ergonomic design that helps them hold up this bag without digging into your shoulders. And though they claim this bag can hold 250x its own weight (which would be over 40 pounds), we wouldn't recommend it for any length of time. The Ultra-Sil requires careful packing to stop from feeling every edge and corner from digging into your back. We found that this pack and other ultralight packs we tested are similar in overall comfort, though they take slightly different approaches to achieve that - rather than using some minimal padding in the shoulder straps, Sea to Summit chose a wide, ergonomic design with no padding.
A lot of a pack's versatility hinges on the usefulness of its features, which the Ultra-Sil is lacking a lot of. This bag is just one zippered pocket and that's about it. There's a tiny loop on top you could clip something to and three fingers-worth of daisy chain on the bottom. If you really want to get inventive (and we bet you do, you ultralight enthusiast!), the tiny stuff pouch that ends up inside the pack could double as a little pocket for your keys. It also comes with a carabiner, which can then be used to attach something to the outside of the bag while it's in use. Other ultralight models retained a few extra pockets that we think make them more useful and versatile than this one.
It's hard to beat a bag that only weighs 2.7 ounces (carabiner included). Even the other ultralight models we tested weigh more, though barely. This weight reduction does come at the cost of those extra features and key areas of padding. But if weight is paramount, the Ultra-Sil is one of the lightest we've ever tested.
Ease of Use
The Ultra-Sil is extremely simple. With 20 liters of internal space, it has just one large compartment that zips wide open for easy access. It's rather easy to lose one small item in just one large compartment though, as we discovered. This pack is also without any corded zipper pulls, which cuts weight, but we found ourselves missing them, as the metal zipper tabs are incredibly short.
One area in which the Ultra-Sil has a slight advantage over other ultralight models we tested, is the size of person it can accommodate. With slightly longer shoulder straps, this pack is easier for taller and larger folks to wear.
Made of 30-Denier ripstop nylon, this pack is the thinnest we tested. Even other ultralights are thicker (though marginally so). That being said, we had no actual issues with this bag during our months of testing. That doesn't mean we'd recommend it as your primary bag to hike through a thorny ecosystem though. If you like lightweight, but don't want to sacrifice quite so much in fabric durability, you might consider some of the other lightweight simple packs we tested that only weigh a few ounces more.
This pack is one of the cheapest we reviewed. For how versatile and portable it is, we think this is a great value. And hey, if you do rip an unfixable hole in that 30-Denier nylon, replacing the whole bag at this price isn't quite so painful.
We appreciate the lengths Sea to Summit has gone to, to create this ultralight, super packable bag that just works. It's not one to load up with heavy or pointy objects or take on a long day out. Though we ultimately like the features included in slightly heavier ultralights just a little bit more, for an on-the-go bag, this one's pretty handy too.
— Maggie Brandenburg
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