Gear Review: WoolX Lightweight Merino Wool Baselayer Series – T-shirt, Hoodie & Boxers

posted in: Gear Reviews, Hiking Gear | 4

Why Buy?

Back in June, I went on my first multi-night backpacking trip in eight years, covering 60+ miles in Sequoia and Kings Canyon National Park on the High Sierra Trail (HST). One of my primary concerns leading into the hike was figuring out what I was going to bring for clothing. Here are some of the things I was thinking about:

  • Temperatures – I needed to carry gear sufficient for temperatures ranging from 20-80° F.
  • Weather – In the High Sierra, rain is common, and it can snow during the summer months. I needed to carry clothing that would keep me warm, even if it got wet
  • Washing Clothes on the trail – being a multi-night trip, I would not be carrying enough clean clothes for the entire hike and would need to do some laundry on the trail. I needed to bring clothing that would dry quickly when washed and ideally clothing wouldn’t need to be washed frequently.

When I initially started planning this hike, I just assumed that most of my layers would consist of synthetic materials, however I had major issue with this: odor. I sweat excessively. While synthetics work well for the gym or day hikes, I can’t wear them for more than an hour or two of strenuous exercise without them smelling horrible the next day. I’ve actually thrown out synthetic shirts because they retain odors even after washing.  With this in mind, I figured I would need to bring 3 t-shirts and 3 pairs of boxers (2 for hiking, 1 pair for sleeping) if using synthetic materials.

I had recently started testing some merino wool socks and was impressed by their antibacterial and wicking properties. I wondered if shirts made of the same material would work just as well. After a few Google searches, I decided that merino shirts could be a good solution. Wikipedia has a good summary of merino’s properties:

Several properties contribute to merino’s popularity for exercise clothing, compared to wool in general and to other types of fabric:

  • Merino is excellent at regulating body temperature, especially when worn against the skin. The wool provides some warmth, without overheating the wearer. It draws moisture (sweat) away from the skin, a phenomenon known as wicking. The fabric is slightly moisture repellent (keratin fibers are hydrophobic at one end and hydrophilic at the other), allowing the user to avoid the feeling of wetness.[8]
  • Like cotton, wool absorbs water (up to 1/3 its weight), but, unlike cotton, wool retains warmth when wet,[9] thus helping wearers avoid hypothermia after sweating from strenuous exercise or getting rained on when outside.[8]
  • Like most wools, merino contains lanolin, which has antibacterial properties.[10]
  • Merino is one of the softest types of wool available, due to finer fibers and smaller scales.[9]
  • Merino has an excellent warmth-to-weight ratio compared to other wools, in part because the smaller fibers have microscopic cortices of dead air, trapping body heat similar to the way a sleeping bag warms its occupant.[11]


I was a little worried about wool shirts and boxers being itchy, but one of the companies I was looking at was very confident in their products and offered a 30-Day 100% No-Itch Guarantee. Here is an excerpt from their website:

WoolX is so sure we have created the softest 100% Merino Wool garment which is absolutely itch-free that we back it with a full 30-Day No-Itch Guarantee. Wear and wash your WoolX garment for up to 30 days. If you decide at anytime during the 30-day period that it isn’t the softest and most itch-free Merino Wool you have ever worn, return it for a full refund. We’ll even pay the shipping back! Just follow the simple 30-Day No-Itch Guarantee return instructions.

Not knowing exactly how well my lightweight merino wool t-shirts and boxers would work, I still took 3 shirts and 3 pairs of boxers on my HST Backpacking Trip. On my backpacking trip, I also brought merino wool shirts and boxers from competitors to get a direct comparison with other products.

My Observations

The observations below include notes from my HST trip and hikes completed since returning from the HST, as well testing at the gym and around the house.

T-shirt (The Outback)

  • The Good
    • The antibacterial and odor resistant qualities of this shirt are amazing (more on this below).
    • The shirt wicks moisture extremely well. During intense cardio session at the gym, I’ve noticed that it appears as though sweat is being pulled through the fabric and beading up on the outside of the shirt.
    • I noticed very little itching when trying the shirt on. After washing the shirt the first time, the itching was gone.
    • After washing it on the trail, the shirt dried very quickly. In the thin air and hot sun of the Sierra, it dried in less than 30 minutes.
    • The shirt can be machine washed and dried – the other merino wool items I own have very particular care instructions (delicate cycle or hand wash, air dry only, etc)
    • More durable than the other 100% merino shirt I purchased. The other shirt developed holes after a 1/2 dozen washes and less use than my WoolX shirts.
  • The Bad
    • More expensive than synthetic shirts, but competitively priced with merino t-shirts from other companies.
  • The Bottom Line
    • If you’re a backpacker, they are worth the investment. When backpacking or going on any trips where being able to wear a shirt multiple days without washing is beneficial, these shirts will find their way into my gym bag, backpack or suitcase. While testing the antibacterial/odor fighting properties of the Outback T-shirt, I had the following conversation with my wife. It nicely sums up the most amazing qualities of this shirt:
      Me: Does this shirt smell?
      Wife (reluctantly sniffs shirt): No, why?
      Me: Would it gross you out if I told you that I’ve already worn it for four days, including 3 hikes and 30+ miles, and I plan on wearing it again today?
      Wife (wide-eyed): ummm, YES!
      Me: Ok, I won’t tell you that then.
      Wife: …

      It’s probably a good thing I didn’t say anything about the boxers I was wearing.

Boxers (Daily Boxers)

In addition to the antibacterial and wicking properties of merino wool, I was also interested in seeing if I would experience any chafing, which has happened with both synthetic and cotton boxers.

  • The Good
    • No chaffing.
    • Like the t-shirt make of the same material, the boxers can be machine washed and dried and dry quickly on the trail.
    • The WoolX boxers hold their shape better than the other boxers I tested. They did not stretch and become loose like the others.
    • I’ve worn them for 2 long days of hiking followed by a weeks’s worth of workouts at the gym without them developing a horrible odor. It may be possible to wear them longer than this without washing, but my wife reads this blog (In fact, I think I heard the washer just start up). 😛
  • The Bad
    • Unlike the other WoolX items I own, the boxers have a sewn-in tag. On my High Sierra Trail hike, I noticed that I had some irritation where the tag touched my skin. I was carrying a heavy pack and noticed more pressure there than normal, so that may been part of the problem. On later hikes with less weight and a different pack, I had no issues.
    • More expensive than synthetic boxers, but competitively priced with merino boxers from other companies.
  • The Bottom Line
    • The simple fact that I’ve hiked close to 100 miles in these boxers and haven’t experienced any chaffing makes them well worth the investment. Chaffing while hiking, especially on a multi-day hike can be very painful.

Hoodie (Base Camp Hoodie)

Please note that I received the WoolX lightweight merino wool hoodie after my HST trip, but am including it in this review since it is made from the same lightweight merino wool.

  • The Good
    • Has the same antibacterial and wicking properties as the t-shirt and boxers and can also be machine washed and dried.
    • Super soft and very comfortable. Most people I’ve shown it to have a hard time believing it’s wool.
    • The thumbholes and hood give it an edge over the other long sleeve shirts I typically use. Most synthetic alternatives have a hood or have thumbholes, but not both. I am excited to test this hoodie once it starts to snow.
  • The Bad
    • More expensive than synthetic wicking hoodies.
  • The Bottom Line
    • It’s my favorite longsleeve shirt. It’s found a permanent spot on my gear list; you’ll find me wearing it to the gym, on hikes in the hot SoCal deserts, and in alpine environments with subfreezing temps.

Final (& somewhat random) Thoughts

  • While I would consider merino wool an expensive option for everyday use, I now consider it a very important part of my layering system for backpacking and hiking trips. My WoolX shirts and boxers have been used in temperatures ranging from 32° (mid-teens with windchill) to over 100° F. 
  • If I had know how well the merino wool was going to work on my HST hike, I would’ve left 1 t-shirt and 1 pair of boxers at home. It may not seem like a ton of weight, but over 60 miles, every little bit adds up weight and volume wise.
  • Since returning from my trip, I’ve been using the t-shirts, boxers and hoodie on a weekly, if not daily, basis. You’ll see me wearing them on the trail, around the house and at the gym.
  • One bonus of using merino wool on a daily basis is less laundry. If you’re conscious of water usage (as most residents of California should be), or just hate doing laundry, it may be something to consider for everyday use.
  • If money were no object, I would replace my gym shirts and the majority of my everyday t-shirts and boxers with WoolX merino.


Disclaimer: The products reviewed in this entry were provided to by WoolX.

4 Responses

  1. jenbeckseymour

    Thank you! Excellent information. I want to check out their underwear for women…

    • TheHikingGeek

      Great – Let me know what you think after you try them!

  2. Asaf

    An excellent and most detailed review! Thanks!

    I’m intrigued as to how you think the Hoodie will do in very warm (~100
    degrees) and humid environments? I own the ExOficio Sol Cool Hoodie
    and use it in that environment with mixed results (good ventilation
    with the mesh panels but poor odor resistance) and would like to
    compare it to the Base Hoodie.



    • TheHikingGeek

      Hi Asaf,

      Since I live in SoCal, I don’t have much experience with the hoodie in humid weather. I contacted WoolX with your question, since I know they have ambassadors that live in humid areas:

      Lightweight wool does have many properties that make it particularly useful in warm, humid conditions. Lightweight Merino Wool is exceptionally breathable and naturally wicks moisture away from the wearer to the surface of the fabric where sweat can evaporate, helping to both cool the wearer and actually making them dryer. Wool can absorb up to 30% of its weight in water and still feel dry to the touch, insuring you won’t get the clammy, clingy feeling you can from synthetic fabrics. Wool also dries more quickly than other natural fabrics.

      Woolx is also much better at odor prevention than any synthetic fabric, the ExOfficio hoodie he mentions is 91% polyester, a fabric that definitely holds onto odor even after washing. We have gotten great feedback from our customers and ambassadors that Woolx merino is particularly good at odor prevention, and I think you can attest to that having worn Woolx over many days hikes! However in hotter, wetter conditions the effect will be tested more and won’t be as pronounced as it is in a less harsh climate. But after laundering Woolx will definitely not hold onto the stink like synthetic fabrics eventually do.

      We randomly had a similar question sent to us from the Ask the Gear Guy columnist at Runner’s World magazine earlier this summer. I had previously sent him some product samples in the hopes of getting Woolx in the magazine and he e-mailed me when he had a reader ask a question about merino wool in humid, hot conditions. One of our product designers/testers, Brian Needels, answered him. Here is the link below:

      To sum up Brian’s response basically he said that merino wool is naturally breathable and moisture wicking and will dry faster than a lot of other fabrics, in particular cotton, but that once you reach a certain level of heat and humidity even merino or other technical fabrics won’t be able to stop you from being hot and sweaty. He does say that in those conditions a wool would still leave you comparatively more comfortable than other fabrics.

      “Also if you’re in a very humid climate, this can really affect the evaporation rate. I would suspect that if the wool is getting saturated, cotton would be five times worse in the same conditions.

      I hope this helps. Please let me know if you have any other questions.