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O'NEILL

O'Neill Men's Thermo-X Long Sleeve Crew-Neck Rashguard Top, UPF 50+ Sun Protection with 4-Way Stretch Thermal Fleece Fabric

  • Based on 261 reviews
Condition: New
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Availability: In Stock.
Fulfilled by Amazon
Arrives Tuesday, Jul 14
Order within 23 hours and 24 minutes
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Size: Medium


Color: Black


Features

  • Other Fibers
  • Imported
  • Skin Cancer Foundation Recommended Product; UPF 50+ Ultraviolet Protection
  • Perfect For Chilly Days When An Extra Layer Of Warmth Under Your Wetsuit Is Needed
  • Thermo-X Layering Fabric Provides Incredible Insulation With Low Bulk And Quik-Dry Properties
  • 220g Nylon/Spandex Includes Water Repellency And Odor Resistance
  • ***Super Low Neck: No Interference With The Neck Of Your Wetsuit

Description

The O’Neill Men’s Thermo-X Long Sleeve Crew delivers quick-dry, lightweight insulation, UV protection, and comfort in and out of the water. Designed with a performance fit, it moves like a second skin for maximum mobility and layering versatility. The U.P.F. 50+ rating shields against harmful rays, while the quick-dry 4-way stretch fabric and flatlock seams add durability and comfort. Featuring Thermo-X HyperDry technology, this top minimizes water absorption while providing insulation and rash protection. Ideal for surfing, swimming, paddling, kayaking, wakeboarding, waterskiing, snorkeling, diving, windsports, or simply enjoying your favorite activity on the water. Thermo-X offers a reliable fit, fresh modern style, and the trusted O’Neill quality that’s built to last.

Color: Black


Swimwear Form Type: Rash Guard


Sleeve Type: Long Sleeve


Style Name: Men's Thermo-x L/S Crew


Swimwear Top Form: Rash Guard Top


Rise Style: Mid Rise


Pattern: Solid


Neck Style: Crew Neck


Apparel Closure Type: Pull On


Strap Type: Non-Adjustable


character: sports


Back Style: Standard


Fit Type: Snug


Material Type: Nylon, Spandex


Lining Description: Thermo-X Fabric


Product Care Instructions: Hand Wash Only


Fabric Type: Other Fibers


Apparel Fabric Stretch: Medium Stretch


Apparel Fabric Weight Class: Medium Weight


Ultraviolet Protection Factor: UPF 50+


Garment Size Country: United States


Size: Medium


Brand Name: O'NEILL


Special Size Type: Standard


Age Range Description: Adult


Style Number: 5022


Global Trade Identification Number: 21


UPC: 191015002421


Number of Items: 1


Manufacturer Part Number: 5022-002-M


Included Components: wetsuit


Manufacturer: O'Neill Wetsuits


Item Type Name: Rash Guards


Unit Count: 1 Count


Sleeve Length Description: Long Sleeve


Fit to Size Sentiment: True to Size


Product Benefits: Sun Protection and Rash Prevention


Frequently asked questions

If you place your order now, the estimated arrival date for this product is: Tuesday, Jul 14

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

    • 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
    • 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.
    • 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.
    • Perfect for snorkeling in Hawaii
Size: XX-Large Color: Black
I’m not allergic to the cold, but in water cooler than the Caribbean I prefer at least a little insulation. We took a trip to Hawaii for the first time and enjoyed snorkeling, and I’m glad I got this to do it in. Fits well, not too loose but not a death grip either (get one size up from your normal tee shirt size), sleeves just long enough to fit my long arms and long enough in the torso it doesn’t ride up like a crop top but not so long it comes down past your pockets. The fleece microfiber lining or whatever it is soaks up water and keeps enough of it against your skin to be warmed by your body and not get too cold too quickly. It’s not a wetsuit of course, actually holding that water against you continuously and not letting it out, but it does seem to help. It definitely doesn’t make it too warm, either, striking a nice balance in temperate waters. ... show more
Reviewed in the United States on June 19, 2021 by Eric H.
    • warm, durable, good fit for thin men except at neck
Size: X-Small Color: Black
Good fit in general for a thin built man but loose at the neck (mine is 14+ and I ordered Small). A lot of water would rush in this gap so I wear a thin rash shirt above. It's warm and so far after about a month in a chlorine pool it seems durable
Reviewed in the United States on December 29, 2025 by dub
    • Good quality. Very warm, fits true to size.
Size: X-Large Color: Black
Good quality. Very warm, fits true to size.
Reviewed in the United States on December 5, 2025 by Dmytro Umanets
    • Effectively protects against cold and wind.
Size: Small Color: Black
The size is just right. I like it when it sticks to the body. It doesn't bother or hinder movements. The clip for the shorts is an excellent feature. Protection against the cold is perfect for me. Before I had lycra, once wet, with the wind, it was worse than nothing at all. Often I had to stop surfing because of the cold, neck and lower back pain. Now I enjoy comfort and surf longer. I am really very happy and I recommend this article. I don't know how it will hold up over time, but it seems to be sturdy. When it's ruined, I'll buy the same one again ... show more
Reviewed in the United States on February 16, 2024 by Marion
    • Use in chlorine pool for water aerobics - works great!
Size: XX-Large Color: Black
I wear this under my swimsuit tank top (I'm a woman) to keep my upper body warm in the winter months while doing water aerobics and water walking in a heated chlorinated pool. So far it is holding up just fine - I have worn it during 24 1-hr sessions and it has not faded, has not stretched, nor is it showing any signs of breaking down. It keeps my upper body and arms comfortably warm. Even though the Thermo-X fabric is quite stretchy, these tops run very small. I am a fairly large woman (usually wear Woman's 2X) and needed to buy a men's 2XL. Because it is a men's, it is a bit snug at the hips, but the rest of it fits well. Fair warning: once wet it is a bit hard to take off, but once you get one arm out of a sleeve, getting the rest of it off is pretty easy. ... show more
Reviewed in the United States on December 11, 2022 by G1

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