HeatGear Long Sleeve Base Layer Top
Product code: T128209T
About this style
This Under Armour baselayer provides premium performance through lightweight HeatGear® fabric. Cut to a regular fit with a compression feel that provides support during activity. The high mock neck offers additional coverage, while strategically placed stretch-mesh panels increase ventilation. Long sleeves and an ergonomic design ensure durability and a locked-in feel for intense training sessions.
Reviews (98)
Active Comfort
Originally posted on Under Armour
Yes, I recommend this
Works really well. Keeps you cool well being active
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Headgear long sleeve sweats
Originally posted on Under Armour
Yes, I recommend this
Amazing fit that was truly worth the wait for. Should be a great fit for under a golf polo in the coming season. Compresses the body well.
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HeatGear
Originally posted on Under Armour
Yes, I recommend this
I don't know what kind of witchcraft these are made of, but it works. Not a traditional warm feel, difficult to describe. The important thing is they make you feel warm!
Helpful?
Fits great
Originally posted on Under Armour
Yes, I recommend this
The size was great. True to size and compresses well for an over weight person who wears Large. The heat is retained and it literally feels like another skin layer. It's really comfortable in the gym
Helpful?
Great material and comfortable
Originally posted on Under Armour
Yes, I recommend this
I usually hate any compression shirts, but since i had to get one for work, this one was very breathable and not as noticeably constricting as other compression shirts. Definitely recommend trying one true-to-size and a size up, especially for bigger guys like me.
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Great product to work out
Originally posted on Under Armour
Yes, I recommend this
I used it to work out and it’s fantastic. It stretches good with the body and holds everything in place
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very well made
Originally posted on Under Armour
Yes, I recommend this
comfortable and keeps you warm
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Heatgear
Originally posted on Under Armour
Yes, I recommend this
As always a great product. No issues
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Not so good
Originally posted on Under Armour
No, I don't recommend this
Big fan of Under Armour Cold Gear mock necks been wearing them for years.I tried the HeatGear mock neck for when the weather isn’t so cold I ordered a couple of colors and I’m very disappointed the mock neck is so loose on both they just don’t fit well at all under clothing.
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Replied
03 January 2026
Hi, Paul! Thank you for being a longtime fan of our ColdGear® mock necks. We truly appreciate your loyalty over the years. We’re sorry to hear the HeatGear® mock neck didn’t deliver the same fit and feel you’ve come to expect. Your feedback about the looser neckline is incredibly helpful, as we're always working to improve!
Great fit
Originally posted on Under Armour
Yes, I recommend this
Under Armour have never, ever disappointed me with its products!! Once again , I love my purchase
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Does fit as described
Originally posted on Under Armour
No, I don't recommend this
Was nowhere near the stated fitment description.
Helpful?
Replied
02 January 2026
Hi! We're so sorry to hear that the fit of the gear wasn't what you were expecting. We totally understand how frustrating that is. Your feedback is very valuable to us, as we are always looking for ways to improve our gear.
This product feels very comfortable
Originally posted on Under Armour
Yes, I recommend this
Product is just as described. Feels great and very breathable. Nice fit. Would highly recommend if your looking for a comfortable compression shirt. Glad to have found this particular product since it is exactly what I was looking for and will purchase another soon.
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Under armour heat gear
Originally posted on Under Armour
Yes, I recommend this
Excited to use it for spring golf and in the fall with cooler temps
Helpful?
Product is very comfortable
Originally posted on Under Armour
Yes, I recommend this
I’m so glad I purchased this item. The feel and comfort of this product is second to none. Keep it up UA!
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Heat gear
Originally posted on Under Armour
Yes, I recommend this
great fit, comfort. Would buy again
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Keeping Warm
Originally posted on Under Armour
Yes, I recommend this
Been looking for some gear to keep warm. Came across UA heat gear and found what I was looking for. The pants and shirt have live up what they are supposed to do, keep me warm. Great product and very happy with the price. Found a new customer!
Helpful?
This product is great for out in the cold weather
Originally posted on Under Armour
Yes, I recommend this
This is my fourth item of this product I love it. I wear it when I walk in the morning in the cold and it holds my body heat inside. excellent product.
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Great fit
Originally posted on Under Armour
Fits well and perfect for martial arts training
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Runs Small
Originally posted on Under Armour
No, I don't recommend this
Very tight even after going up a size. Very thin layer also.
Helpful?
Replied
27 December 2025
Hi, Jose! We're bummed to hear that the fit was too tight, even after sizing up. We totally understand how frustrating that is. We also want you to feel your best when rocking your gear, so it sounds like we've got some work to do! I'll be reaching out via email shortly to get some additional details. Talk to you soon!
This product is great.
Originally posted on Under Armour
Yes, I recommend this
The product is very stretchy and provides good warmth. Love the material that it is made out of it’s very comfortable.
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