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LAPASA Men's Thermal Underwear Bottom Long Johns Pants Base Layer Lightweight Midweight Heavyweight Cold Weather M10/M25/M56

  • Based on 6,995 reviews
Condition: New
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Availability: In Stock.
Fulfilled by Amazon

Arrives Wednesday, Dec 25
Order within 22 hours and 23 minutes
Available payment plans shown during checkout

Team Name: Thermoflux 300 Heavyweight


Athlete: 1 Pack


Size: X-Large


Color: Black


Department ‏ : ‎ mens


Date First Available ‏ : ‎ June 5, 2023


Frequently asked questions

If you place your order now, the estimated arrival date for this product is: Wednesday, Dec 25

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


  • Excellent product
Team Name: Thermoflux 300 Heavyweight Athlete: 1 Pack Size: X-Large Color: Black
People are different. Some may say I'm a baby, but who cares. I can take the heat, but not the cold. In the cold I feel as if my bones are going to break in half. Because I'm not use to the cold weather. So I really wanted to put this item to the test. So what I did was as soon as I opened the package, I washed it in warm water and put them into the dryer to see if they would shrink, and also to see how much of the fleece would come off on the dryer screen since I dried them inside out. There was only 6 tiny little lint particles. In the meantime, I took a shower because I didn't want to put them on while being uncleaned. So what I did was, I waited for the underwear to be completely cool not to be influenced by the warmth of the dryer I also waited for my body to reach room temperature not to be influenced by the warm shower, then what I did was I put them on over my boxers instead of putting them on by themselves like some have done. There was no warmth of the dryer it was cool to the touch like I wanted so that I could see for sure how well it keeps me warm. As soon as I put them on, there was a huge difference with the room temperature fleece against my body. They are smooth inside and out and without the waffle pattern that long johns have. According to the news, and my digital thermometer, the outdoor temperature 🌡️ was 51 degrees I also checked my car's outdoor temperature and the dashboard read 1 degree more at 52 degrees. For others this is nothing. But for me on a clear night without any cloud cover it's freezing. But NOT when I had them on. You see, when I went to the car to check the temperature on the dashboard, the only thing I had on was a long sleeve thermal shirt, a pair of boxer shorts, the heavyweight thermal fleeced long johns, slippers without wearing any socks, and my N95 mask. I wasn't embarrassed going out there with my long johns because they look like a pair of gym pants. Oh sure you know that they have a fly, but it looks so natural. Besides, it was covered by the length of the thermal shirt. No one would ever know. I could have went to the store etc. etc. They look like men's tights that they use at the gym. Anyway, while outside, My body didn't feel the cold. They really do work. The only thing that was cold was my ankles, feet, (since I had no socks on) the part of my face that was not covered by the mask, and my head. I then put on a pair of pants over the thermal long johns and went outside again to see the difference, and there was a huge difference. Obviously, I was even warmer. Great product. Thank you. G.C. ... show more
Reviewed in the United States on November 11, 2020 by G.C.

  • Very thick, warm and comfortable.
Team Name: Thermoflux 300 Heavyweight Athlete: 1 Pack Size: Large Color: Camouflage Dark Gray
I love them! Bought two pieces of the tickest kind available. I use them everyday under my regular pants when riding my motorcycle in winter weather. Will buy some more when needed. Very recommended item. Worth every dollar I paid for them. MC
Reviewed in the United States on January 24, 2024 by Manuel Cisneros Jr. Manuel Cisneros Jr.

  • Warm
Team Name: Thermoflux 300 Heavyweight Athlete: 1 Pack Size: X-Large Color: Black
Well made product, properly sized and above all warm and soft, happy with the purchase
Reviewed in the United States on February 23, 2024 by Peter

  • Toasty! Great fit.
These are for temperatures below freezing. I slipped a pair of breathable golf kakis over these and play when the ground is frozen. The waistband comes up to my belly button allowing me to tuck in a long-sleeve water wicking tee shirt in deeply and put on a lightweight hoodie that falls over the underwear and pant waistband sealed by a lightweight shell. I pull the underwear over my sox. Everything stays in place the higher waistband rides higher then the pants waistband preventing bunching. I love these! I returned 3 other brands for size, nonwarmth, low waistband that bunched and serious shrinkage. This underwear is exactly how I would design it. Perfect! ... show more
Reviewed in the United States on March 1, 2024 by J. MOORE

  • Best longjohns I ever had!
Best longjohns I ever had! Super comfortable, super warm, AWSOME! They do run a little small so order big.
Reviewed in the United States on January 18, 2024 by Dano

  • Great fabric
I wanted another pair of lightweight longies and these have exceeded my expectations. Great fabric and the cut of them fits me just right. We’ll see how they hold up.
Reviewed in the United States on January 19, 2024 by Ke

  • Decent quality
Team Name: Thermoflux 300 Heavyweight Athlete: 1 Pack Size: Large Color: Olive
The leggings are quite loose but that's okay. Most importantly they are warm and don't get lint fast. We’ll see the durability with time, cause you never know how soon that tricky tear might show up
Reviewed in the United States on January 28, 2024 by Valeriya

  • Runs Large, Doesn't fit as snug as traditional long-johns/leggings.
Material seems to be nice, it's wicked soft and warm but these don't fit as tight as normal long-johns or leggings, etc. I'm 6'0" and ~150lbs, got Mediums and they were loose in the legs (good in waist/ankles), got Smalls and same thing. Comfortable but not sure how warm they'll keep me when they're not tight to my body. Granted, I'm a real slim dude but...small sized leggings/long-johns should be tighter. ... show more
Reviewed in the United States on December 14, 2023 by Amazon Customer

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