Men's Original Fit Longsleeve Crewneck

This men's long sleeve cotton t-shirt is perfect for managing cold sweats or helping you stay dry and comfortable under layers or sportswear.

Wear the Thompson Tee long sleeve undershirt beneath your favorite hoodie, snow jacket, button-down, uniform or scrubs to add an extra layer of warmth and keep your pits dry.

Our long sleeve undershirt boasts the same sweat proof technology you know and love, just made for colder weather.

The Thompson Tee long sleeve undershirt has the same fit and feel of a traditional undershirt.

Proprietary design blocks sweat from pentrating clothing and showing through your underarms.

Center seam with separate front and back sweat panels for a sleek, tailored fit and feel.

Patented Hydro-Shield sweat proof technology won't wash out or lose effectiveness over time. Prevent pit stains day after day, wash after wash.

Move through your day freely. Thompson Tee's long, tuckable length stays in place all day. So go ahead and wave those arms around!

The Thompson Tee is the original sweat proof undershirt.

It's the only undershirt backed by a patent from the U.S. Patent and Trademark Office for our Hydro-Shield sweat proof technology, which completely absorbs and blocks sweat while maintaining breathability. Although others might say "sweat proof," no undershirt can protect you like the proven Thompson Tee, and no other shirt has patented technology to back up such a claim.

Here are a few of the features that make our sweat proof undershirts unique:

• Proprietary layering and stitching system blocks sweat from seeping through your underarms.
• Sweat proof technology won’t wash out or lose effectiveness over time.
• Separate front and back panels to trap sweat effectively, minimize heat build-up and keep you feeling cool.
• The underarm barriers are created with a center seam design for a sleek, smooth fit that doesn’t bunch under your clothing.

The shirt and size you choose will ultimately depend on your fit and style preferences.

Both our Men’s and Women’s Slim Fit shirts are made with rayon from bamboo and are intended to fit snug, so they’re more discreet underneath your clothing.

The Original Fit is made from 100% premium combed cotton and provides a little more breathing room for those who prefer a looser undershirt. If you're looking for the most sweat protection but like the fit of a typical T-shirt, you may want to try a size up in the Original Fit shirts.

Either way, both options come with our proprietary Hydro-Shield Sweat Proof Technology, backed by our Sweat Proof Guarantee!

For the complete guide to choosing the right Thompson Tee size and style for you, check out our blog here.

YES - We didn't just call it "sweat proof." We earned it! The Thompson Tee is the only patented proprietary design that uses a clinical-grade sweat proof material that completely blocks moisture from passing through. Other shirts may advertise "sweat proof" but don’t hold moisture well. They typically consist of two cotton layers and are often treated with chemicals that could wash out over time. The benefits of our sweat proof technology are native properties, so the shirt will not lose its effectiveness over time. That's why every Thompson Tee with Hydro-Shield Sweat Proof Technology comes with a Sweat Proof Guarantee. We guarantee that your underarm sweat won’t penetrate the sweat proof barrier — or your money back!

While armpit pads and sweat shields may absorb some sweat, they do not allow moisture to evaporate. So throughout the day, armpit pads can lose their stickiness due to sweat or become heavy and bulky beneath your shirt.

Unlike sweat shields, garment guards and sweat pads, Thompson Tee's sweat proof barrier is the only patented sweat proof technology available. By trapping sweat and releasing it through evaporation, your sweat won't show through your outerwear. Plus, you won't have to worry about adjusting your sweat pad or changing it out for a new one throughout the day.

For more in-depth information on sweat pads and sweat shields, check out our page dedicated to the topic here.