Seirus sent us a bunch of their specialized outdoor socks to test in our Lightweight Footwear Systems for Snow Travel project (link in sidebar). These included the NeoSock and SuperSock which are neoprene water-resistant/breathable socks, and their StormSock and Hyperlite StormSock which are a weatherproof/breathable three-layer construction. How well did they perform for keeping feet warm and dry while snow hiking and snowshoeing?
Specialized socks from Seirus we evaluated are (left to right) Outlast Liner Sock, NeoSock, SuperSock, StormSock, and Hyperlite StormSock.
We used the Seirus Outlast Liner Sock in a wide variety of footwear systems as a first layer to wick moisture away from the skin. We went to the Outlast website to find out what the Outlast technology is all about, and conclude it’s a “black box”, meaning the manufacturer’s explanation of it is very vague: “Tiny ‘microencapsulated Thermocules’ spun directly into yarns absorb and store excess heat, and release it when you need it most.” Now you know as much as we do! All the hype aside, we found the Seirus Outlast Liner Sock to be high quality, warm for its weight, and very versatile
The other Seirus socks we evaluated are confusing because the names are so similar, so we will cover them as two pairs of similar socks to distinguish them.
NeoSock and SuperSock
The NeoSock is 3 millimeter thick neoprene with a thin four-way stretch nylon fabric on the outside and a thin stretch polyester on the inside. The SuperSock is 2 millimeter thick neoprene with the same face fabric and lining but the inside color is red instead of black. The only difference is in the thickness of the neoprene layer. Both socks have lots of stretch.
The Seirus NeoSock (top) and SuperSock Bottom) are highly breathable neoprene, and are not waterproof. The right sock is turned inside out in the photos to the left. The photos to the right show a close-up of the outside and inside fabrics.
These socks are claimed to be “highly breathable” and water-resistant, so they are basically insulating socks. We performed our “balloon test” (blow up a sock by mouth, pinch off the top, squeeze the air out through the fabric) on these socks, and found they breathed very well. In our “immersion test” for waterproofness (stuff a sock with a white cotton T-shirt, submerge it up to the ankle in a pan of water for an hour, inspect the T-shirt for wetness), they easily wetted through and soaked the T-shirt. Our results verify that they are highly breathable and non-waterproof, so we conclude their main purpose is breathable insulation.
They are sized to fit snug on the feet, kind of like wetsuit socks. Worn directly against the skin when snow hiking or snowshoeing, the socks feel warm at first, but soon feel clammy and chilly from sweat held inside. We much preferred to wear liner socks inside them, but there was barely enough room because of their snug fit, so they were a bit too tight, which is not good for keeping feet warm. To wear these socks comfortably, we recommend sizing up one size so they fit comfortably over a liner sock or thin wool sock. It’s also necessary to wear these socks inside a boot or shoe that is fairly waterproof, otherwise they will wet through from the outside. The bottom-line for us – we would prefer to wear wool socks instead of neoprene socks. However, neoprene socks are worth considering when the amount of space is very limited, e.g., ski boots.
The Seirus SuperSock (shown) and NeoSock (not shown) are stretchy neoprene and are designed to be worn against the skin as an insulating sock. We found they breathe very well, but feel clammy against the skin, so it’s best to size up and wear a liner sock under them.
StormSock and Hyperlite StormSock
These socks are completely different from the neoprene socks discussed above. The StormSocks are made of two versions of Seirus’s Weather Shield tri-laminate fabric. The StormSock has a weatherproof/breathable membrane sandwiched between a durable four-way stretch Nylon fabric on the outside and a polyester fleece lining on the inside, and the Hyperlite StormSock has a four-way stretch Nylon and Spandex fabric on the outside and a thin polyester fleece lining on the inside.
The Seirus StormSock (top) and Hyperlite StormSock (bottom) are a waterproof/breathable three-layer construction. The StormSock is fleece-lined, while the Hyperlite StormSock is thinner and stretchier. The right sock is turned inside out in the photos to the left. The photos to the right show a close-up of the outside and inside fabrics.
In contrast to the neoprene socks, these socks are comfortable to wear against the skin because of their fleece lining. They are also sized for a snug fit, so there is little room to wear liner socks inside, unless you size up to accommodate them.
These socks are claimed to be weatherproof/breathable. The term “weatherproof” is a bit vague, and implies that the socks are waterproof; they are not. Our “balloon test” on these socks found they breathed fairly well. However, the socks do not appear to be seam-sealed so the air could have escaped through the seams under pressure. Our “immersion test” revealed that these socks easily wetted through and soaked the T-shirt inside. We conclude that these socks are not waterproof but they are breathable. The next step is to evaluate how “weatherproof” they are.
We snowshoed, snow hiked, and summer hiked in very wet conditions wearing the StormSocks (with and without a liner sock inside them) in non-waterproof trail running shoes. The combination kept our feet warm at first while hiking in wet snow or wet vegetation at warmer temperatures, but they soon wetted through and our toes got cold. The leakage was primarily in the toe area and amounted to only 0.3 to 0.4 ounce of water per sock when we weighed them, but it was plenty to cause chilly toes. We found no evidence that the seams are taped, so the leakage most likely occurred through the sewn seams. Thus, our field tests agree with our “lab” tests, and conclude that these socks have no use as a waterproof/breathable sock.
Since these socks are fairly breathable and not waterproof, we tested them in non-waterproof boots while snowshoeing and walking in cold dry snow. Under those conditions boots stay mostly dry, and the StormSocks were effective as a (semi) vapor barrier to keep our feet warmer and restrain moisture from entering our wool insulating socks. We say “semi vapor barrier because they are not seam-sealed, and they allow a bit of moisture to migrate into our insulating socks worn over them. We conclude they are most useful worn against the skin as a vapor barrier sock in cold and frigid conditions. Such a system worn in frigid temperatures will help keep feet warmer, but it would allow a small amount of moisture (from sweat) to migrate into insulating socks and the shoe lining. The Seirus StormSocks also fit much better than other vapor barrier socks we reviewed.
We wore the Seirus StormSocks (Hyperlite StormSock shown) while snowshoeing, snow hiking, and summer hiking in very wet conditions. They leaked, and our toes got damp and cold, so they have no use as a waterproof/breathable sock. They performed much better as a vapor barrier sock in cold and frigid conditions.
Overall, we cannot recommend neoprene socks to keep feet dry and warm while snow hiking and snowshoeing. The cannot compete with a good pair of merino wool socks for insulation and moisture managemen. The weatherproof/breathable Stormsocks perform as a vapor barrier in cold and frigid conditions. A totally waterproof vapor barrier sock would function slightly better, but we did not find any that fit nearly as well as the StormSocks. Because these socks are thin, they would also be useful in situations where there is very limited room, such as a ski boot.
Specifications and Features
- Manufacturer: Seirus Innovation (www.seirus.com)
- Sizes: Men’s and Women’s S,M,L,XL
- Fabric: NeoSock and SuperSock are neoprene with a thin four-way stretch nylon fabric on the outside and a thin stretch polyester on the inside, StormSock and Hyperlite StormSock are a three-layer construction consisting of a nylon/Spandex face fabric, membrane and fleece lining (StormSock) or tricot lining (Hyperlite StormSock)
- Features: Fitted, two-way stretch, flat seams
- Weight: Measured weight/pair for size Large: NeoSock 3.7 oz (105 g), SuperSock 3.2 oz (91 g), StormSock 2.7 oz (77 g), Hyperlite StormSock 1.7 oz (48 g); manufacturer specification NeoSock n/a, SuperSock 4.8oz/pair (136 g), StormSock 4.0 oz/pair (113 g), and Hyperlite 2.4oz/pair (68 g)
- MSRP: NeoSock and SuperSock $21, StormSock and Hyperlite StormSock $26