Field Tested: Seirus Heatwave Winter Weight Baselayers

by
posted on December 12, 2024
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Heatwave Lede

Of all the wintertime trials I put my gear through, few things test the true cold-weather functionality of a garment better than whitetail hunting. When you're ranging across the hills, glassing after elk or muley, you can get away with dressing a little lighter. In the blind, however, on an all day sit? There's something about the way circulation drops after those first few hours that ensure you'll catch a chill in all but the warmest of clothing. I can safely say, however, that I've found a new baselayer more than up to the challenge—Seirus Heatwave Winter Weight Baselayers. To make sure of it, I toted it to Saskatchewan this November for some all-day whitetail sits.

Now of course, the Heatwave Baselayers were not solely responsible for my comfort—I had insulated or woolen outerwear on as well. That said, I know roughly how warm that setup generally keeps me on an all day sit, and I'd be lying if I said a chill didn't eventually creep in. Not so with Heatwave. Despite temperatures dipping into the high teens and low 20s some days, I got no colder than I would have sitting in my own living room.

So how does it accomplish this? The secret really is in the name. Heatwave is not simply the name of the baselayer, but the name of the technology it uses too. Upon first handling the clothing, you'll notice what appears to be a semi-reflective sheen coming off of it. This is the Heatwave tech, which is designed to reflect 20-percent of body heat right back at you, leading to an increase in heat retention of some four to five degrees. This property allows the baselayers to remain thin and comfortable, without giving up warmth. Wicking fabric is also included to prevent sweating, while power mesh increases breathability at perspiration zones. In case you do plan to wear these on a more active hunt, spandex is integrated to keep the whole thing flexible, with Flatrock, anti-chaff seams.

While the garments are sure to keep your core and legs warm, the secondary effect of such comfort is improved circulation, which can keep your toes and fingers from freezing prematurely—indeed, several of the days I was comfortable enough to take my gloves off when temperatures hit the high 20s.

The verdict? If you're looking for a comfortable way to spend the late season this year, pick up a Crew Top and Bottom Heatwave Winter Weight Baselayer set from Seirus. You wont regret it. seirus.com; $99.99/Crew Top; $89.99/Bottom

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