Good to know: This is a unisex pack
Pros / Reasons to Buy
- Incredibly lightweight
- Amazing packability
Cons / Reasons to Avoid
- Offers no padding or real support
- Maximum weight you can carry is 7kg
The Sea to Summit Ultra-Sil 20 is a divisive pack – some people love it and others, not so much. After testing we actually found we generally liked it, but that is only when you use it in the way it is intended.
It’s important to remember that this isn’t a standard hiking pack with suspension support, nor is it intended for full on use. It’s intended for extremely lightweight hikes, travel and shopping and is a good grab and go when you need it.
This likely won’t be the only hiking daypack you need, but if you want something that can be used in a variety of settings and covers all your bases, then you will likely be impressed with the Ultra-Sil 20’s weight and flexibility.
Editor’s note: This article is part of our overall guide to the best daypacks, see more in this guide:
- Best Daypacks for Hiking
- How to Choose The Right Daypack For Your Hike
- How We Tested Hiking Daypacks
- Compare Hiking Daypacks
You may also be interested in: Best Waterproof Hiking Backpacks
Compare to Similar Products:
Product | Osprey Talon 22 | Gregory Maya 25 | Deuter Speed Lite 23 | Osprey Stratos 24 | Gregory Citro 24 | Rab Tensor 20 | Osprey Daylite/Plus | Mystery Ranch Coulee 30 | Black Diamond Distance 15 | The North Face Basin 24L | Sea to Summit Ultra-Sil 20 | Cotopaxi 24L Batac Pack | Granite Gear Dagger Ultralight | Rab Adrift 24L | Adidas Terrex Climacool Daypack | Cotopaxi Luzon Del Dia 24L |
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Buying Options | ||||||||||||||||
Our Award | Best Overall Daypack | Best Overall Daypack - runner up | Best Daypacks For Women | Best Daypacks For Men | Best Waterproof Hiking Daypack | Best Daypack For Hot Weather | Best Daypack For Travel | Best Hiking Daypack With Hydration | Best Lightweight Daypack | |||||||
Type and Style | Lightweight all purpose backpack for hiking, climbing and bikepacking | Active hikes, longer trails, climbing | Hybrid trail running/hiking/climbing | Full suspension backpack | Full suspension hiking pack | Lightweight summer pack | Lightweight lifestyle travel/hiking pack | Full suspension backpack/summit pack | Hybrid trail running/hiking/climbing | Hiking and biking | Ultralight daypack | Basic hiking | All round hiking | Fully waterproof hiking | Basic hiking, travel and general day to day use | Basic hiking, general everyday use, travel |
Material | bluesign®-approved recycled 100D x 210D wave check high-tenacity nylon with a PFC-free DWR coating. | 100D 30% recycled high density nylon, 200D 45% recycled high density nylon | 140D and 100D recycled polyamide | 210D recycled nylon body, 420D recycled nylon accents and bottom with a PFC/PFAS-free DWR | 210D Honeycomb Cryptorip Nylon and 420D High Density Nylon body. EVA foam straps, alloy steel frame. 135D High Density and 50% recycled polyester lining | 100% recycled 420D polyester ripstop | bluesign® approved 300D recycled polyester | 210D recycled nylon, DWR | UHMWPE ripstop body fabric and mesh | 210D recycled ripstop nylon and 600D recycled polyester also all with non PFC DWR | 15D high strength nano nylon fabric with silicon coating for water resistance | Offcut material used from other brands production runs, making a sustainable pack | Nylon (100D and 210D) | PFAS Free ripstop nylon | 100% recycled polyester | Offcut material used from other brands production runs, making a sustainable pack |
Capacity | 22 liters | 25 | 23L | 24L | 24 liters | 20 liters | 20 liters | 30L | 15L | 24L | 20L | 24L | 22L | 24L | 32L | 24L |
Breathability | Excellent | Excellent | Excellent | Excellent | Excellent | Excellent | Not as good as some other models | OK | OK | Not as good as some other models | Poor | OK | Good | OK | OK | OK |
Pockets | 6 | 9 | 9 | 6 | 7 | 7 | 8 | 7 | 11 | 6 | 1 | 6 | 6/7 | 7 | 6 | 5 |
Dimensions | 48 x 28 x 23 cm | 50.8 x 28.4 x 23.3 cm | 52 x 27 x 18 cm | 59 x 34 x 24cm | 52 x 28 x 20 cm | 50 x 30 x 23cm | 43 x 26 x 20 cm | 57 x 27 x 24 cm | 47 x 32 x 13 cm | 50 x 27.9 x 17 cm | 48 x 28 x 20 cm | 51 x 28 x 18 cm | 53.34 x 33.02 x 20.32 cm | 52 x 30 x 25 cm | 50 x 26.5 x 17 cm | 60 x 30 x 17 cm |
Rain Cover | No | No | No | Yes | Yes | No | No | No | No | Yes | No | No | No | No - but the daypack is already waterproof | No | No |
Durability | Excellent | Excellent | Excellent | Excellent | Excellent | Excellent | Excellent | Excellent | Good | Excellent | OK | Good | Excellent | Excellent | Good | Good |
See the Sea to Summit Ultra-Sil 20 in more detail:
Analysis and Test Results
This is an ultralight daypack in the greatest sense of the word – it weighs in at 72g/2.5oz, which is by far the lightest in our round up. Minimalists will likely love this pack for ultralight missions.
Though that does come at a cost – there is little to no padding or structure in this pack, so you have to pack it really well in order for it to be comfortable. Whilst it can also hold 20 liters in volume, it is recommended not to fill it over 7kg (which I agree with) so it does have its limits.
That said, it does come in at a very low price point and is a versatile, on the go solution that doesn’t just work well for hiking. But travel, shopping and day to day use when the time calls for it too.
Performance Comparison
Type and Style
The Sea to Summit Ultra-Sil 20 really does sit there in the ultralightweight and minimalist category. Coming in at 72g/2.5oz you really can’t argue with the fact that it literally weighs nothing.
It’s actually a very versatile pack for the weight too. Some hikers will love this because of its weight combination and packability (it packs down into a small pouch) as it can be used on bigger backpacking missions. It’s a great option for taking off on day hikes whilst you’re already camped up. It also works great for travel and for shopping too.
Material
The Sea to Summit Ultra-Sil 20 makes use of a 15D high strength nano nylon fabric for pretty much its entire construction. It also uses a silicon coating to provide a level of water resistance. Through my tests, I did find this worked pretty well against trail abrasions and I also found that the water resistance works well on all but harsh storms.
So, this pack should have you covered for most eventualities. I wouldn’t really recommend taking the pack in really thorny or bushy areas though, as you might hit the limits of the fabric’s durability.
Breathability
This pack really is lightweight and as mentioned removes a lot of the fabrics and techniques used to help improve breathability. Obviously, it doesn’t have anything by way of a suspension or an air vent system, so this does impact breathability.
I used this pack on a variety of summer hikes in hot conditions and I didn’t actually find the breathability (and sweating) I experienced were too bad considering the pack and what it’s intended for. This was helped by ensuring I was wearing a tech fabric t-shirt though, which I would recommend when using this pack in hotter conditions.
Waterproofing
The Sea to Summit Ultra-Sil 20 isn’t waterproof, but water resistant, so it will keep out rain to a point, but for anything heavy, it will reach saturation. I’ve tested this pack in a variety of weathers and it has worked pretty well against the rain.
I would avoid packing anything really valuable or important in this pack if you’re planning to use it in inclement weather. However, given that this pack has a recommended fill weight of 7kg, I don’t think this will really be an issue.
Dimensions
The pack when unpacked from its smaller size for carrying is 28x20x48cm/11×7.9×18.9 inches. This does give you a good amount of room to play with and is actually comparable to a lot of the other packs in our best hiking daypacks round up.
This also makes it pretty useable when it comes to travel as well – and fits within a lot of airlines guidance for carry-on luggage/personal item (though you should of course check this with your airline before travel). When packed down, it fits comfortably in your hand, and can easily be attached to your belt or similar for things like shopping. It can easily be stowed on or in a backpacking pack if you want something easily to grab for day hikes from your base camp.
Fit
Because of the fact that this is such a lightweight pack, Sea to Summit have compromised on a lot of areas, and the fit is one of them. They have made an effort to make sure that the straps are wider though, which does help well with weight distribution.
I found that if this pack wasn’t packed properly, it feels like it droops and pulls on the back, which is pretty uncomfortable. With this in mind, it also sits a little lower than I would often like for a hiking daypack.
So, it’s important to make sure you only carry up to 7kg, but I’d make sure these are generally just extra layers! If you’re carrying water, it really sags more (and this has to be stowed inside the main pack).
Storage
The Sea to Summit Ultra-Sil 20 makes use of pretty much just one main storage compartment, which is zipped up. This really is a no frills pack, and if this suits you, you will be pretty well served by it.
Sea to Summit only recommend fitting up to 7kg of weight into the pack, and from my tests, I would say I agree with this. Anything further and it just feels too uncomfortable and not good to hike with.
Comfort
If you’re seriously considering buying this daypack, you really need to keep in mind that it has absolutely no padding at all. I found when testing it that the only way to get it to sit comfortably is to pack it well.
This happened by putting my padded layers near the back, but it didn’t feel ideal and didn’t provide a great weight distribution experience. If you want to bring heavier or bulky gear, this may put this pack out of the running for you.
The one saving grace of this completely unpadded pack is the wider straps which do help with weight distribution. I feel this pack will suit you well if you really want to go hardcore with your ultralight gear, but I wouldn’t recommend it for longer treks.
Features
One of the reasons that the Sea to Summit Ultra-Sil 20 is able to come in at such a minimalistic feel and weight is because it has stripped back on most of the features you will likely be used to with a day pack. That said, one of its main features is that it can be packed up exceptionally small and carried with a carabiner for ease of use.
This makes it ideal if you want an on the go pack for things other than hiking too. Or you want something that is suitable to put into a backpacking pack for day missions on longer adventures. It also uses a siliconized nylon fabric that adds water resistance. Though I wouldn’t rely on it not to saturate in heavy downpours.
Durability
This pack is by far one of the thinnest packs on the market, and it certainly does feel that way. The 15D high strength nano nylon fabric does seem to do a good job of protecting it from abrasions on the trail though.
I think it’s important to remember that this pack does not come in at a particularly expensive price point, and nor does it claim to be a really supportive pack. Once I started to use it for what it was intended for, which is fast and light quick hikes, I started to find it worked pretty well.
The saving grace of this pack is its weight, and obviously there are quite a few sacrifices here in terms of durability. I think it’s likely that this won’t be your only pack, but if you are looking for something extremely lightweight, then this may well suit your needs.
Sustainability
Sea to Summit, like many brands have a sustainability section on their website, which talks about how they’re striving to make themselves a more sustainable company. However, the Ultra-Sil 20 doesn’t contain any (named) recycled materials at present and there is no detailed information about their production process for this pack.
There’s also the fact that whilst this pack can be handy if used correctly, it is likely not going to be your only daypack, which does mean buying more. I’m also not confident how long the materials used for the body of the pack will hold out through trail conditions. This ultimately has an impact on sustainability.
Conclusion
The Sea to Summit Ultra-Sil 20 is a good minimalist option for hikers who want to have a quick and easy pack to go for when it comes to fast and light hikes. It’s pretty amazing what Sea to Summit have managed to do with this pack in terms of weight (72g/2.5oz) but this does come at a cost.
If you’re looking for something as your main daypack, or you want a pack that will hold heavy and bulky equipment, then this won’t be for you. It’s also contains no padding so you will need to make sure you pack it well and don’t overfill.
However, if you want a versatile pack that can fold down to virtually nothing for travel, a quick pack for hiking off the cuff or as a secondary pack for backpacking once you’ve set up camp at a cheaper price point, then you will likely enjoy what the Ultra-Sil 20 has to offer.
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