August 12, 2020
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Without proper gear, sweat can be our own worst enemy in the heat. So what do we wear when it’s hot? Polartec works hard to stay at the cutting edge of fabric technology and has spent years working to solve this issue — The result is Polartec® Delta™, a base layer fabric engineered for evaporative cooling so the body can optimize its natural cooling process, sweat.

Delta’s innovative cooling technology enables fantastic performance shirts designed for all kinds of warm-weather activities. Our partners have gone above and beyond with our Delta fabric, designing some of the best lightweight performance shirts available on the market. We’ve compiled a list of our favorite uses of Delta from some of the best outdoor brands across the globe. Check out our Featured Fabric article to learn more about Delta and how it works.

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Rhone Notch Performance Piqué Tee

Using the same Delta piqué mesh fabric as their polos, Rhone created a band-collar design with a small placket. The result is a pared-down take on the classic polo that's still more elevated than a standard tee. Best used for sunny days, warm nights, and anything in between.

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Fox Flexair Delta Short Sleeve Jersey / Flexair Delta Long Sleeve Jersey

On hot and humid days, mountain bikers need a jersey that works as hard as they do. There's no better option than Fox’s Flexair Delta collection. Though they won a 2017 Apex award for their original Delta jersey, Fox kept pushing their cooling jersey design to create the greatest collection of Delta MTB Jerseys on the market.

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Pas Normal Solitude Mesh Jersey

The Solitude Mesh Jersey from Pas Normal is made for the hardest days on the bike, when you demand as much from your kit as you do your body. Cut entirely from Delta, the jersey more effectively utilizes the body's natural cooling process than jerseys in the past.

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Reigning Champ Polartec® Delta™ Polo / T-Shirt / Long Sleeve

Reigning Champ features the piqué knit version of Delta in three performance style tops: polo, t-shirt, and long sleeve shirt. With this collection, Reigning Champ lives up to its name as the global standard in premium athletic wear.

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Roark Shelter Long Sleeve Pullover Knit

Roark earns bragging rights for creating the first sun hoodie made with Delta. In recent years, product designers have tried to reimagine the classic hoodie for added UV protection in the summer sun. Roark found that Delta is the perfect solution. Their Delta sun hoodie offers the coverage of a sweater but with the evaporative cooling capabilities of the best warm-weather training shirts.

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Slam C141

On deck we have the C141 t-shirt by Slam. Delta ensures a lightweight, breathable design that dries quickly and absorbs humidity. The raglan cut of the sleeves has a nautical flair and keeps water out, keeping you dry and cool from sun up to pipe down.

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Crazy T-shirt Delta Woman

Call us crazy, but these women’s mountain tees are incredibly stylish. Dubbed the most technical t-shirt in the Mountain Women’s collection due to Delta’s evaporative cooling function, this t-shirt from Crazy is suitable for most intense outdoor activities.

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Millet Trilogy Delta Polo

The Trilogy Delta Polo from Millet is designed to keep you dry on excursions, treks, and summer mountain hikes. This polo's ergonomic design and quick-drying properties are suitable for backpack wearing as it provides the best next-to-skin comfort.

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Castelli Active Cooling Sleeveless

This base layer is perfect for road biking on a hot day. By using hydrophilic and hydrophobic yarns, this sleeveless top holds a bit of moisture next to your body while its special open knit allows free airflow through the fabric. You get evaporative cooling directly on your skin.

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Oiselle Flyout Racer Back Tank / Short Sleeve

Oiselle’s Flyout™ tops are made with the classic radiator Delta fabric that “hovers” over the skin, moving sweat up and away to keep you dry. Our Product team insists that these tops are the best women’s Delta products on the market.

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Beretta Polo Flash Tech

Look like a pro, shoot like a pro. The Flash Tech polo, developed in new generation lightweight and breathable technical fabrics like Delta and Power Dry, pays homage to the Beretta Team athletes with the team's print on the back.

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Kjus Sami Polo S/S

Fore! Look out for this Sami golf Polo from Kjus because it may get you that birdie under the sun. Kjus calls Delta “the secret weapon” for its innovative polo as it can cool down your body temperature and protect you from harmful UV rays for a day on the links.

To learn more about Delta and how it works, read our Featured Fabric article.

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