O'Neill Thermo X Long Sleeve Rash Guard Medium
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O'Neill Thermo X Long Sleeve Rash Guard Medium

SKU: ONLTXLTMD MFR: 5022-002-M
(17)1 question, 1 answer
$71.95

Key Features

  • Enjoy superior comfort with this O'Neill rash guard, perfect for all-day wear.
  • Stay protected from the sun's harmful rays; this rash guard offers UV protection.
  • The breathable fabric of this long sleeve rash guard keeps you cool and dry.
  • Flatlock seams on this durable rash guard ensure chafe-free water sports sessions.
  • This quick drying rash guard is ideal for surfing, snorkeling, and more!
  • Move freely; the snug fit of this stylish rash guard enhances your performance.
See More Product Details
Temporarily On Backorder?Expected Availability: 09/2025Request assistance or get notified
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Questions & Answers

Shopper : Why Did You Choose This?Tim S : I am going to e wearing this under my 5mm Camaro Front Zip Alpha 5 suit in December in the northern Bahamas (75 - 78] degree water temperature). All my other O'Neill products have all been excellent!! I have no reservations in believing the rash guard will wear & work as good as all the others.

Reviews about this item

Review Summary

2024-03-10T20:00:00

Rated 5 out of 5

Review of great thermal.

Do they also come in a turtle neck ?

James H.

2023-11-25T19:00:00

Rated 5 out of 5

Cute and comfy

He wears specifically for this time at the year

Paz R.

2023-04-13T20:00:00

Rated 5 out of 5

Great!

Great!

Jeronimo C.

2023-02-10T19:00:00

Rated 5 out of 5

I love it being 65

I love it being 65 I get cold faster this has helped extend my time in the water coupled with a 4-3 chest zip O'Neil

Mac B.

2023-01-26T19:00:00

Rated 5 out of 5

Drysuit Underwear Top

This top replaces one that is at least 10 years old. I use it underneath my O'Neill Fluid drysuit ( unfortunately no longer made by O'Neill ). The Thermo crew is very comfortable and fits me well. I'm 6'3 and 193 lbs. great garment that I recommend

W J.

2023-01-21T19:00:00

Rated 5 out of 5

Feels great

Feels great

Christopher M.

2022-12-23T19:00:00

Rated 5 out of 5

Magical!!

Not awesome but magical. This fabric should be used to line gloves, socks and booties. I?m a cold water swimmer at Walden Pond in Concord, MA. I was in last week with snow and air/ water at 29/39. When I finished an hour swim and doffed the wetsuit I was able to stand in the sun with just the Thermo and Speedo and felt warm. It doesn?t hold water so when you doff it and shake it?s like a water spray that comes off. If the whole graphene thing works this product would be a natural fit.

Rocky T.

2022-11-30T19:00:00

Rated 5 out of 5

Warm shoulders in the winter?s cold

I wear the thermo top and am able to swim no Matter how Cold it is outside. Such a great discovery!

Laurie G.

2022-10-07T20:00:00

Rated 4 out of 5

I like this for many

I like this for many reason. Warm, comfortable, fits well. Only draw back is, how much water it holds. Took it off first time and realized how heavy it is when its soaking wet. Probably not needed for warm Hawaii waters.

John F.

2022-04-29T20:00:00

Rated 5 out of 5

Great addition

Light and comfortable, worked great taking the chill out and avoiding a rash.

Jayson E.

2022-04-08T20:00:00

Rated 5 out of 5

????

????

Francisco C.

2022-01-20T19:00:00

Rated 5 out of 5

recommend this product

recommend this product

Bryan M.

2021-12-23T19:00:00

Rated 5 out of 5

Great for a Tri Top

I use it with my sleeveless tri suit. This is my second. I swim daily in the Atlantic where the water temps range from 90 in August to 45 in Feb. Works great as a jelly guard - cannonballs to box jellies.

Kenneth P.

2021-11-23T19:00:00

Rated 5 out of 5

The warmth I needed

It's a La Nina year and the waters off Ecuador get colder. I wore the Thermo-x L/S under my shorty wetsuit and was able to snorkel for an hour. Others with regular rash guards were coming out much earlier.

Edward J.

2021-10-08T20:00:00

Rated 4 out of 5

Almost Great

It fits, but could fit better if it were more tailored. I don't know if that's possible given the material. Goes on and off easily and is free moving. We'll see how long it lasts..

todd k.

2021-03-06T19:00:00

Rated 5 out of 5

Awesome warmth

Awesome warmth

Chris M.

2020-12-21T19:00:00

Rated 4 out of 5

Like all your products that

Like all your products that I have used for over 50 years, GOOD QUALITY and I expect that it will last.

Gary G.

O'Neill Thermo X Long Sleeve Rash Guard Specifications

  • Type

    Rash Guard

  • Materials

    220g Nylon/Spandex

  • Waterproof

    No, Repellent

  • Breathable

    Yes

  • Moisture Wicking

    Yes

  • UV Protection

    Yes

  • Closure

    None, Pull-Over, Boardshort Connector

  • Construction

    Flatlock Stitched Seams

  • UPC Code

    191015009734

Oneill Men's Apparel Size Chart
  X-Small Small Medium Large X-Large 2X-Large 3X-Large
Weight (lbs) 125-140 135-155 150-170 170-190 190-210 210-230 230-250
Chest (in) 30-32 34-36 38-40 42-44 46-48 50-52 52-54
Waist (in) 22-24 26-28 30-32 34-36 38-40 42-44 44-46

About O'Neill Thermo X Long Sleeve Rash Guard

FEATURED REVIEWS

Great for a Tri Top

By Kenneth P.

I use it with my sleeveless tri suit. This is my second. I swim daily in the Atlantic where the water temps range from 90 in August to 45 in Feb. Works great as a jelly guard - cannonballs to box jellies.

Great addition

By Jayson E.

Light and comfortable, worked great taking the chill out and avoiding a rash.

The O'Neill Thermo X Long Sleeve Rash Guard is made from Thermo-X layering fabrics and provides incredible insulation with low bulk and quick-dry properties. Maximum base-layer insulation with 4-way stretch fabric adds extreme comfort and freedom of movement. This water repellency rash protector has strategic seam placement, a super low neck so there's no interference with the wetsuit neck. Ride-up is prevent with the use of a boardshort connector. Made from 220g nylon/spandex with HyperDry for maximum insulation and minimal water absorption. The Thermo-X HyperDry material has flatlock stitched breathable seams that provide strength durability and comfort. Rash Guard is available in multiple sizes.

O'Neill Thermo X Long Sleeve Rash Guard Features

  • Thermo X Long Sleeve Rash Guard:
  • Layering Fabrics
  • Provides Incredible Insulation w/Low Bulk & Quick-Dry Properties
  • Maximum Base-Layer Insulation w/4-Way Stretch Fabric
  • Fabric Adds Extreme Comfort & Freedom of Movement
  • Water Repellency Rash Protector, Strategic Seam Placement
  • Super Low Neck: No Interference w/Wetsuit Collar
  • Ride-Up Prevented w/Boardshort Connector
  • Material: 220g Nylon/Spandex
  • HyperDry for Maximum Insulation & Minimal Water Absorption
  • Flatlock Stitched Breathable Seams Provide Strength, Durability & Comfort
  • Available in Multiple Sizes

Warranty Information

This product has a limited warranty of 12 months.

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More About SunnySports

Key Features

  • Enjoy superior comfort with this O'Neill rash guard, perfect for all-day wear.
  • Stay protected from the sun's harmful rays; this rash guard offers UV protection.
  • The breathable fabric of this long sleeve rash guard keeps you cool and dry.
  • Flatlock seams on this durable rash guard ensure chafe-free water sports sessions.
  • This quick drying rash guard is ideal for surfing, snorkeling, and more!
  • Move freely; the snug fit of this stylish rash guard enhances your performance.

What's in the box:

  • Thermo X Long Sleeve Rash Guard
  • MFG 1 Year Limited Warranty