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O'Neill Men's Thermo X Long Sleeve Insulative Top

  • Based on 282 reviews
Condition: New
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Availability: In Stock.
Fulfilled by Amazon

Arrives Tuesday, Dec 23
Order within 2 hours and 17 minutes
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Size: X-Large


Color: Black


Description

Thermo-X layering fabrics provide incredible insulation with low bulk and quick-dry properties.

Package Dimensions ‏ : ‎ 20.52 x 14.07 x 3.61 inches


Item model number ‏ : ‎ 5022


Department ‏ : ‎ mens


Date First Available ‏ : ‎ December 13, 2017


Manufacturer ‏ : ‎ O'Neill Wetsuits


Frequently asked questions

If you place your order now, the estimated arrival date for this product is: Tuesday, Dec 23

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


  • Awesome!
Size: XX-Large Color: Black
Works great! I teach swim lessons outdoors in the winter and this has kept my top half from freezing. I tried the women’s one first but it was too tight across my shoulders. Guy one fits like a glove
Reviewed in the United States on April 3, 2025 by Nicole

  • Fits better than a glove
Size: Large Color: Black
I only buy O'Neill wetsuit products as I find they are the only company whose size chart is accurate for me. This is a well made thin wetsuit long sleeve top that fits like a glove. You won't even know you're wearing it outside of the warmth it provides. It's ideal for this early fall days when the temperatures begin to fall and these's some wind....Mobility, paddling, is excellent..like I said You wouldn't know you're wearing a wetsuit top. ... show more
Reviewed in the United States on November 3, 2024 by Amazon Customer

  • Wonderful for cold days
Size: Large Color: Black
This shirt exceeded my expectations. I swim laps outdoors and it's gotten cold. This shirt makes it lot more comfortable on cold or rainy days at the pool. Like another reviewer suggested, I ordered one size larger than I typically wear. It is snug so the water doesn't pump too much and it is a little difficult to get off but it works well. I'm about 145 pounds, 5'-9'' and I ordered a large. ... show more
Reviewed in the United States on December 19, 2024 by Nancy P.

  • Wow, This Really Works
Size: X-Large Color: Black
I've never bought a rash guard or insulative top before, but we just bought a new house with a big pool and it's just too cold outside of the summer months and too expensive to heat. I'm a bigger guy and the XL fit great. It's thick and spongy but not heavy. I had no idea what to expect. It does not constrict any movement. I kind of look cool wearing it, and even gives me a little slimming look, if I do say so myself. I can easily get into a cool pool and at first I feel just a bit of the coldness, but in 15 or 20 seconds, its great! I spend 30 to 60 minutes in the pool after 5PM and it never loses the insulating effect. It's easy to get off and it dries super quick, just letting it hang over the balcony. I'm not sending a picture, because I don't think anyone wants to see that, BUT I for sure recommend this. Saw ones that were TONS more expensive. Don't know how much better those are, but like I said this one works GREAT!!! ... show more
Reviewed in the United States on September 18, 2020 by Darren_707

  • Fits Snugly, Gets Heavy
Size: Large Color: Black
The O'Neill Men's Thermo X Long Sleeve Insulative Top is designed to fit tightly, so consider buying your normal size. It provides good insulation, but it can get heavy when wet with water. Overall, it's effective for keeping warm in colder conditions.
Reviewed in the United States on July 12, 2024 by ndrwum

  • Great fit. And it works. By it's self or under a wetsuit I stay warm!
Size: Medium Color: Black
Perfect for those days when it's not cold enough for a wetsuit, but you still want to stay warm! And when it's really cold, I wear it under my wetsuit for a little extra warmth!
Reviewed in the United States on November 25, 2024 by Alastair T

  • Warm and well made
Size: Large Color: Black
Own a bunch of O’Neill rashguards so naturally picked up a Thermo X for fall/winter. It’s basically what I would call a quarter mil rashguard as it’s slightly bulkier than their standard rashguards given the slightly thicker material with fleece lining. It’s thinner than 0.5mm tops though so 0.25mm seems like a fair description. No issue with movement restrictions. I wear this under a union suit that is under my dry suit for kayaking. Have been down in 20s on the water and not slightly bit cold whatsoever. Works exactly like I hoped. I have some thermal compression shirts I bought for this particular use case and picked this up afterwards. While the compression shirts are warm they sit a tad looser, nothing crazy but noticeably different fit as this sits tighter on body. But the Thermo X is definitely warmer, sometimes paying up is well worth it, this is one of those times. ... show more
Reviewed in the United States on November 20, 2023 by W. A.

  • Nothing
Size: XX-Large Color: Black
I like everything about the product
Reviewed in the United States on November 5, 2024 by Amazon Customer

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