When goggles list 'Rx Insert Included,' it means they come with a prescription lens frame that snaps in behind the goggle's main lens. You take this insert to your optometrist to have your custom prescription fitted to it, so you get clear vision without wearing your regular glasses underneath.
This is a big upgrade over OTG (Over-The-Glasses) goggles for a couple reasons. First, it eliminates the double-fog problem—when you wear glasses inside goggles, moisture gets trapped between the two lenses and fogs up fast. Second, the insert sits closer to your face, giving you better peripheral vision and a more comfortable, secure fit. The only trade-off is that the insert takes up a small amount of interior volume, so it can feel slightly snugger against your nose and cheeks.
If you wear glasses daily and want the most hassle-free vision solution on the mountain, goggles with an included Rx insert are a smart choice. Just remember you'll still pay your optometrist to fill the prescription—the insert itself is simply included in the box.