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Merino.tech

Merino.tech 100% Merino Wool Base Layer Mens - Thermal Underwear Long Johns

Based on 3,633 reviews
Condition: New
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$58.49
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Availability: Only 5 left in stock, order soon!
Fulfilled by Amazon
Arrives Wednesday, Oct 28
Order within 4 hours and 36 minutes

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At a glance

Condition
New
Size
X-Large
Color
. 320 Charcoal Grey
Material
100% Superfine Merino Wool
Style Name
Modern/Fitted
Rise Style
Mid Rise
Leg Style
Skinny

Specs 43

Package Dimensions 10 x 9 x 0.7 inches; 4.8 ounces
Item model number 165
Department mens
Color . 320 Charcoal Grey
Style Name Modern/Fitted
Rise Style Mid Rise
Leg Style Skinny
Fit Type Standard

Frequently asked questions

If you place your order now, the estimated arrival date for this product is: Wednesday, Oct 28

Yes, absolutely! You may return this product for a full refund within 30 days of receiving it.

To initiate a return, please visit our Returns Center.

View our full returns policy here.

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Top Amazon Reviews

Warm, and Good for Layering, and Great for Cold Rides!
Size: Medium Color: .Black 250
I picked up the medium black 250 and it’s been perfect for cold weather riding and chilly workdays. I’m 5'10" and 180 lbs, and while the fit is a bit loose, the length is perfect. After 2 years of regular use, it’s still going strong—just a minor hole at the ankle, easily hidden by socks. Pros: ✅ Great Cold-Weather Warmth (250 Weight) – Warm enough that I haven’t needed to upgrade to 320 ✅ Ideal for Motorcycle Rides & Cold Work Days – Keeps me warm without bulk ✅ Socks Are High Quality – Cozy and well-made ✅ Durable Over Time – Still in good shape after 2 years Cons: ❌ Slightly Loose Fit (Medium on 5'10", 180 lbs) – Not overly baggy, just not snug ❌ Minor Wear – Small hole near ankle, but nothing major Final Thoughts: Whether you’re riding in the cold or braving freezing temps at work, this base layer does the job exceptionally well. Warm, breathable, and built to last—an excellent investment for cold-weather comfort. ... show more
Reviewed in the United States on April 30, 2025 by Cyborgladiator
Best long johns I've ever owned !
Size: Medium Color: . 320 Black
The Merino Wool Base Layer Mens Bottom Pants are very warm, soft and comfy. I bought the Heavyweight, 320g bottoms, and I was worried about them being too thick, they're not that thick at all, they are perfect, very, very comfortable and warm. I was golfing with them in 40 degree weather with 12 mph wind and my legs were not cold at all, plus they were not too warm either, actually just right. I didn't where anything but a t-shirt, polo shirt, and light wind proof Foot Joy golf jacket on top, but my chest and arms were not as comfy warm, as my legs were, even though I was wearing thin golf pants over the Merino bottoms. I live in a cold, northern, climate and have bought many, many, different types of "long Johns" and these are by far the best I've ever bought. When it comes to bottom layer long johns, I think they should be snug, but not too tight, I have a 33 inch waist and a 32 inch inseam and their medium size fit me perfect! ... show more
Reviewed in the United States on October 14, 2025 by Rich B.
Well made, warm, good fit, cozy
Size: Small Color: 320 Navy
It's really nice being so toasty warm and feeling so cozy like I'm in my pajamas when I'm out in my work clothes. Super soft 100% merino wool thermals feels so good and soft against your skin. Very functional and I really appreciate that they're not too loose to be baggy and not too tight so the fabric doesn't pull on my leg hairs and is not itchy at all. I didn't know how warm they would be and considered the 250 gm. but I'm really glad I got the 320s because they're not too warm for up north where I am. I do have several shirts of different weights so I can layer to whatever warmth I need and stay warm with just a heavy sweatshirt over them in the northern winter. That's a lot of great value for such reasonably priced, sturdy and durable feeling, odor free, 100% merino wool! I highly recommend merino.tec 320,100% merino wool thermal base layer. You won't be disappointed! ... show more
Reviewed in the United States on November 27, 2024 by Richard S
Excellent product - very comfortable, very warm but I wish the waistband was better
Size: 3X-Large Color: 165 Black
Still the best wool, under-clothes layer I've purchased. Very comfortable, great fit and I will buy again. I do wish it had a wider waist band. That's the only thing letting this product down.
Reviewed in the United States on December 31, 2024 by Scott D. Thoms
Perfect warm and comfy
I wear these 8 months out of the year in Montana. Perfect warmth outside, without being too hot inside. I get everything Merinotec now. Best prices for great wool products. Love the varied wool weight (thickness) selections. Good products though made in China.
Reviewed in the United States on September 9, 2025 by Todd W
Great budget base layer
Size: Large Color: Windsor Blue 250
After buying a set of these for myself, I bought them for my husband as well. They’re warm but lightweight and fit well under snow pants for skiing or snow sports. The quality is good and the elastic holds well for several days of skiing. They wash well - I’ve used the washer on delicate and hang dried to avoid any shrinking or pilling. ... show more
Reviewed in the United States on August 21, 2025 by Emma
Good idea...
Size: Large Color: 165 Burgundy
These are fantastic! Light, warm and don't weigh much at all. Feel great against the skin.
Reviewed in the United States on October 17, 2025 by Beach Brother
Fits true to size.
Size: Large Color: . 320 Black
Very warm and comfortable. Exceeds expectations. Fits true to size.
Reviewed in the United States on October 29, 2025 by stacy shaw
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