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Warm When Wet: The Secret Behind First Lite’s Merino Wool Magic

First Lite wool layers(Photo/First Lite)
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First Lite chose merino wool for the base of its layering systems for several hunting-friendly traits. Then it ‘supercharged’ that wool with unique nylon it says fights odors and dries faster.

Thanks to a blend of fibers with exclusive 37.5 technology cooked in, First Lite Aerowool adds durability and faster wicking from nylon without its usual odor-trapping qualities.

We talked with Ben Flandro, First Lite VP of product and design, to find out why the brand geeks out about this magic-like material. Beyond that, let’s run through some highlights of the hunting apparel collection.

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First Lite wool baselayers
(Photo/First Lite)

Benefits of Merino for Hunters

So why wool? First off, merino fibers resist odor-causing bacteria. That prevents trapping your scent in your clothes while hunting wild game that uses smell as its first line of defense.

Then there’s the range of temperatures that wool allows your body to feel comfortable in, regulating body temperature and wicking moisture away when you begin to sweat. That means it can insulate while a hunter sits still, yet breathe when they’re on the move.

Unlike many synthetics, wool absorbs light rather than reflects it. Wool is also naturally quiet, unlike the noisy friction of other materials rubbing together while walking. Again, wool wins for its hunting performance.

First Lite: 37.5 Merino Wool

Pure wool’s weaknesses are its fragility and its tendency to bog down when wet. A common strategy for apparel makers to bolster a garment is to blend wool with synthetic fibers, often looping the wool around a tougher, nylon thread.

First Lite approaches things differently, using nylon infused with 37.5 technology. Rather than wrapping wool around the nylon, it blends them so that both materials are exposed to the outside.

“By keeping both wool and nylon on the outside, you’re not sacrificing the 37.5 nylon’s wicking and drying performance,” Flandro said.

He found that adding 37.5 nylon into the First Lite Wick fabrics enables them to dry 10 times faster than pure merino. Additionally, whether it’s wet from sweat or rain, the wool will continue to retain your body heat while it dries out.

“You have the odor capture and odor release qualities of 37.5 to then supercharge the merino,” he explained. “We get a really durable fiber that dries faster and doesn’t lose any of the beneficial properties of the merino.”

The 37.5 technology gets its name from the “ideal” core temp of 37.5 degrees Celsius. The rationale is that’s the body’s ideal operating temperature, meaning it doesn’t have to waste energy sweating to cool down or shivering to warm up.

Thus, wearing more layers with the tech makes the system work that much better.

First Lite WICK wool layers
(Photo/First Lite)

3 Weights of Merino

First Lite makes three styles of base layers, in three weights of wool. These are roughly intended for warm, cold, and very cold weather. Its Aerowool category has 37.5 technology, while its other two weights for colder temperatures leverage the insulating benefits of pure merino fabrics.

Here’s a short guide to the brand’s different weights and some of its top-selling wool apparel.

These descriptions are loose guidelines. First Lite knows some of us run warmer or cooler than others, and it promotes wearing these layers as part of a modular system that includes its pants and jackets.

Wick: Ultralight 150 Aerowool is a warm-weather jersey knit that prioritizes wicking and fast dry times. Here, First Lite challenges you to see how wool performs compared to polyester layers in the fall.

Kiln: Midweight 250 Merino-X layers have that in-between weight and warmth that offers versatility in how they’re worn. Kiln layers can insulate on top of next-to-skin layers or become that base layer in cooler climates. These get a touch of spandex to prevent sagging over days of use.

Furnace: EXP 350 Merino-X layers are heavier and use an interlock knit with a brushed interior that’s more open and airy, trapping body heat when worn with a layer over top. When temps rise, the looser knit should allow more airflow. The spandex is there to help the layers retain their shape and fit over dayslong hunts.

“Imagine if the most comfortable sweatshirt you’ve ever owned suddenly got superpowers,” Flandro said, adding that you can wear it while hunting, camping, and skiing.

First Lite Wool Layers

Wick Game Bag Brief

First Lite Wick Game Bag Brief

First Lite puts its Aerowool Wick 150 merino fabric in these briefs with a support pouch that uses mesh sidewalls to keep the guys cool and dry. The briefs have a 7-inch or 8-inch inseam, depending on the size, and have a fly.

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Wick Short Sleeve Crew

First Lite Wick Tee

The Men’s Wick Ultralight 150 Aerowool Short Sleeve Crew shirt with 37.5 active particle technology is designed to dry fast without harboring odors. Areas prone to sweat have mesh panels made with lighter, 125g Aerowool mesh panels to improve breathability and dry times.

Other popular men’s configurations include the Hoody and a Quarter-Zip. The raglan sleeves are positioned away from the usual area for backpack shoulder straps.

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Kiln Long John

First Lite Kiln Long John wool

The Kiln 250gsm Merino-X construction has a slightly more relaxed base layer fit with an interlock knit to help insulate and retain body heat. Comfort-minded design touches include flatlock seams, a functional fly, and a Jacquard waistband.

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Kiln Hoody — Men’s & Women’s

First Lite Kiln Hoody baselayer

A successor to the brand’s bestselling Chama, the Kiln Hoody fits true to size with 18.5-micron, superfine wool against the skin. Its 250-weight wool makeup, hood, and thumbholes check lots of midlayer boxes so it can be worn on its own in shoulder seasons and as a base in the coldest weather.

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Furnace Quarter-Zip — Men’s & Women’s

Kiln and Furnace Quarter Zips wool baselayers

While perched, zip up and take comfort in the high collar and brushed fleece against the skin. On the move, the Furnace Quarter-Zip lets you release heat quickly. The interlock knit wool outside insulates while still being breathable. The flatlock seams and sleeve placement should play well with other layers and bag straps.

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Furnace Zip-Off Boot Top

First Lite Furnace Boot Top baselayers

Customers asked for zip-offs, and First Lite listened. The Furnace Zip-Off Boot Tops are a removable thermal layer for when midday temps creep too high, which is especially common during Western hunts. The easy-access design lets you shed base layers without taking off your boots and pants. The Zip-Off feature is also available in the Fuse Boot Top Long John and Kiln Long John.

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Beyond the Hunt

First Lite designs its wool layers for hunting, but you can enjoy the performance benefits anywhere. Even its designers wear these layers when ski touring in the mountains or running errands in daily life.

Remember to think of these base layers as part of a system. Consider how they will work with other layers, whether you tend to run hot or cold, and where you’ll be hunting.

The part you might like most about wearing wool layers is their adaptability. And First Lite thinks its 37.5-charged Aerowool and cool-weather Merino-X add to that performance.

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This article is sponsored by First Lite Hunting Apparel. Find out more about its merino wool layers online.

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