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Swift Tech Mockneck LS

Swift Tech Mockneck LS

Thermoregulating, moisture dispersing technical base layer with odor resistance

W's Swift Tech Mockneck LS in Atlantic
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Gabby wears size S and is 5'08" Slim fit, Size Chart

The Swift Tech Mockneck LS is a an ultra-soft, moisture-wicking, alpine inspired base layer with the enhanced benefits of merino and Polygiene® anti-odor control. Designed for repeat use between washes, you can wear it as a stand alone top or as your bottom layer. Read more

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Moisture-wicking comfort
Ultra-soft, thermoregulating merino/poly jersey provides fast moisture-wicking management to quickly move sweat + heat away for comfort during prolonged efforts

Stays fresher longer
Polygiene® permanent anti-odor control keeps the fabric fresher for longer, so you can use it more between washing — reducing water + energy consumption

Quick dry
DriRelease jersey speeds up dry times

Wear it on its own or as a base
A snug but not skin-tight fit makes for super easy layering and wearability on its own

Ergonomic seaming
Contoured arm hole with racerback seams allow for freedom of movement

Alpine inspired styling
Mockneck style adds extra neck protection with our signature tonal ladder stitch on back

Better thumb slits
Integrated thumb slits built into the cuffs essentially disappear when not in use

Hang it up
An elastic locker loop is integrated into the back collar 

materials + specs

Swift Tech with Polygiene® anti-odor control
84% polyester, 11% merino, 5% spandex drirelease

162g / 5.7oz (W’s Small)

Garment made in Vietnam


Swift Tech is treated with Polygiene® anti-odor control to inhibit and prevent the growth of bacteria that causes stink. Studies show that washing and caring for garments makes up 2/3 of the environmental footprint over the lifespan of apparel — by wearing more and washing less, even just wearing something twice between washes, can save energy and water, reduce CO2 emissions and minimize micro-plastics.

Swift Tech is also OEKO-TEX® certified meaning it is free from harmful chemicals and is fabricated in a way that meets a high environmental standard.

Learn more about our sustainable initiatives here.


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Customer Reviews

Based on 38 reviews
Wyn P.
Wear it for: Running
Product Fit: Spot-on
Usual Size: S
Size Purchased: S
Great tech shirt

I bought this for my wife. This is one of her go-to’s for running.

Alex M.
Product Fit: Spot-on
Height: 5'10" to 6'0"
Usual Size: M
Size Purchased: M
Love this shirt

It arrived yesterday and I was praying it was worth the wait. Put it on today and OMG! Definitely worth the wait. I'm buying another one today. This is my favorite piece of clothing. Even thinking about taking up running.

Seadar D.

W's Swift Tech Mockneck LS in Atlantic

Jill L.
Amazing workout shirt

Really love this shirt -- wish it came in more colors! Perfect as a base layer for skiing and working out in cold weather. Material feels high quality.

Perfect Base

I was searching for a light weight wool base, and found it! The top is a great base layer for winter trail running. The mockneck keeps out the cold, and thumbholes keep the sleeves in place while layering up. I purchased my normal size, and the sizing was right on. I've worn it multiple times, as soon as it comes out of the wash! The Atlantic is a beautiful color. Well done Janji!


This is my first mockneck and I love it. I wish there were more colors to choose from. I read the reviews and got a size up. I am 5'6 and 128lbs and usually go for a small. I went for medium and it fits like a small. I wear it as a baselayer or under a running vest during cold runs. It's soft and very comfortable.

Theresa W.
Soft and warm!

Great base layer for cold weather running.

Super Warm!

This lightweight shirt is much warmer than I expected from how thick it is. I got mine a size bigger so I can take off if I get too warm. Its been comfy with just a shell down to 10F!

Rebecca S.
Love this top

Soft, anti stink, great for running, snowboarding and lounging. Please keep making it

Flora E.
Great shirt

It's warm for cool weather and is a great base layer. It's also very breathable and soft.