Since Smith Optics released the I/O goggle three years back, they have been my go-to eyewear for a number of reasons. First and foremost: the lenses. Optical clarity, especially in the humid and often greybird conditions of my home in the Pacific Northwest, the Sensor Mirror lenses are hard to beat. Add in the fact that they come with a second lens—in my case a good all-rounder, the Ignitor Mirror—and you can still make out a few shadows in most lighting conditions, even when it’s getting pea-soupy in the alpine.

This leads to the second great advantage of the I/O: easy interchangeability, which doesn’t suck. Let me expand—preceding interchangeable goggle designs had been gimmicky, finicky, and pretty awful when it comes down to staying closed and keeping snow out. In 200-plus days wearing the I/O over the past couple seasons, I’ve never experienced face-shot-induced snow inside the lens. Enough said. Add to the fact that they’re low profile with none of the oversized bug-eye look that you may expect with interchangeable goggles, and, in fact, even less bulk than many standard options. Venting also remains dialed in, and the only way I’ve gotten them to fog is hiking with them on my head/around my neck which is a dumb move anyways, or snow inside the goggles after a good tomahawk.

And, lastly, the fit is also hard to beat. Enough room around the nose to keep them comfy, not too much to look ridiculous. Maybe not the best choice if you’re the type that wants to goggle sag, but I’d rather have goggles that fit. Coupled with a Smith Maze helmet for the last couple years—the lightest certified snow helmet around—it’s a seamless, low-profile package that keeps my head warm, goggles on and vision clear.

Add to it the custom graphics of the special edition Mt Baker Legendary Banked Slalom goggle pictured, and I don’t need another pair of goggles—except maybe a second pair of I/O’s in the pack in case of emergency.

Undoubtedly frequency Approved.