Summer is officially in full swing, which means outdoor adventurers are trading in their puffies for wind shells and fleeces for tees. But as things heat up, not even a lightweight jacket or typical wicking tee can keep athletes completely free from an uncomfortable buildup of perspiration.

You’ve probably heard of Polartec for our world-class insulation technologies and athlete-favorited fleece materials. All-season outdoorspeople trust our products to keep them warm, safe, dry – and cool. That’s right, even cool. In colder climates, warmth and weather protection is crucial to staying safe. But as temperatures change and our outdoor activities evolve alongside them, we recognized a need to give adventurers the same safety and dryness they’ve come to expect from our products, with a cool twist.

Thirty-five years after inventing synthetic fleece, we shifted our fabric engineering expertise to a problem at the opposite end of the thermometer: how to stay cool in hot weather. Polartec® Product Manager Karen Beattie was inspired to create Polartec® DeltaTM because she hated how sweaty fabric stuck to her skin during summer runs and mountain bike rides. She knew what made a great fabric for cold weather. What if she turned the dials the other direction?

After 18 months of research and development, Polartec® DeltaTM cooling fabric was ready for primetime.

How It Works

Delta works in concert with your body to keep you cool. The fabric’s permanent mechanical wicking construction uses two different yarns, one hydrophobic and one hydrophilic, to prolong the skin’s natural evaporative cooling response without chemical additives. The inherent cooling power of this fabric continues to work wash after wash, workout after workout.

The two yarns each have a mission. The hydrophilic (water loving) Tencel yarn holds sweat near your skin, recreating that refreshing feeling of childhood romps through the sprinkler on a hot day. The hydrophobic (water hating) polyester yarn cluster creates an open window for body moisture vapor to escape, maintaining a high level of breathability. The radiator patterned knit is raised to hover over your skin, eliminating the sweaty cling and chafe points found in other hot weather fabrics.

That means that when you’re pushing yourself through a high-exertion exercise, Polartec® DeltaTM actually uses your sweat to cool you down by holding it close to your skin, while still allowing excess heat to breathe through the fabric. This fabric acts like your personal hand-held misting fan.

Who It's Useful For

All kinds of warm-weather outdoorspeople can feel the benefits of Polartec® DeltaTM:

—Trail runners want Polartec® DeltaTM on long, hot training days when they have to manage high heart rates and hours of perspiration.

—Yogis bending and twisting outside in the heat will appreciate how Polartec® DeltaTM hovers over the skin, disappearing from thought and allowing all focus on the poses.

—Mountain bikers reach for Polartec® DeltaTM for grueling ascents or fast sunbaked trails where they can’t catch a break to cool themselves off.

Where You Can Find It

At Outdoor Research, you can find Polartec® DeltaTM cooling technology in each of our Gauge Tees. In addition to regulating core temperatures with DeltaTM, the Gauge collection uses an anti-chafing design, anti-odor fabric, and UPF 15 protection to keep adventurers protected from the sun’s harmful rays. Feeling is believing, which is why so many people and publications recommend our line of Polartec® DeltaTM Gauge Tees for all of your high-output outdoor summer activities.

Gear Junkie ranked the Gauge at the top of their Emerging Gear list, celebrating its hydrophilic cooling technology for hot weather.

Runner’s World tested the Gauge themselves and said that during “a brutally hot summer, the soft fabric never became soggy or bouncy.”

—Finally, the Gauge made the Editor’s Choice list from Gear Patrol’s ranking of Best of Outdoor Retailer Summer 2016.

Don’t let sweat get you down. Check out the entire Polartec® DeltaTM collection from Outdoor Research today.

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