I’ve owned a pair of Smith Knowledge Turbo OTG Fan Goggles for a couple of years now. They have a built-in battery-powered exhaust fan which prevents fogging, which can a real problem on winter hikes when you need to wear full face protection in high wind. Available in a OTG size for people with glasses, and well as a regular (non-OTG) version, they’re my goto hiking goggles when I need protect my face against frostbite on above-treeline hikes.
Before I got these Smith Knowledge Turbo Fan Goggles, my goggles and glasses would often fog up on winter hikes, forcing me to turn around before reaching the summit. This happened the first time I tried to climb Mt Washington in winter which was a big disappointment for me, since we were so close to the top. There was a period of time after that hike where I carried two pairs of goggles on high-exposure above-treeline hikes, so I’d always have a second pair of goggles available if the first pair fogged up.
Since I switched to these Smith goggles, my fogging issues have disappeared. I’m still careful not to wear my goggles on my forehead before they’re needed, which often causes moisture/sweat buildup and can lead to uncontrollable fogging. I also don’t put my goggles on until they’re really needed, usually because I have to wear them with a full Serius facemask and balaclava, which I’d rather avoid as long as possible since it’s so claustrophobic and cuts down on my peripheral vision.
But once I put my Turbo Fan Goggles on and switch on the fan, they stay clear and unfogged, which is great because I have the added complication of being a glasses wearer. The secret sauce is the tiny exhaust fan built into the center of the goggle, which vents moist air and prevents it from condensing inside of the goggle.
You have the option of turning the fan on or off, or running it on a high or low setting depending on your needs. It just requires two AAA batteries: I recommend you use a Lithium Ion type like the Energizer Ultimate Lithium which are cold resistant for winter use and very long-lasting. There’s also a tiny switch on top of the battery housing which locks the power off, so you can’t inadvertently run down the battery when the fan is not in use.
When the fan is in operation, it makes a gentle whirring sound. But the sound is so low, that I can still hear what people around me are saying even though I’m also wearing a full balaclava over my ears.
The weight of the goggles with the battery is just 6.0 ounces. Smith claims that the batteries last for 50 hours before requiring a change, even when the fan is run continuously on a high setting. The goggles also have a dual lens and are coated with an anti-fogging agent inside for further anti-fogging prevention.
Over the years, I tried other goggles and a variety of liquid and paste coatings to keep my goggles from fogging up on winter hikes above treeline, but none of them have proven to be as reliably fog-free as my Smith Knowledge Turbo Fan OTG Goggles, Highly recommended!
Disclosure: The author purchased this product with his own funds.
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