The Knowledge OTGs are equipped with an adjustable regulator system to provide control of airflow through the goggle; open the regulator while in line or on the lift to increase the circulation of dry, fresh air, and close it before descending to prevent exposure to wind. Compatible with the ODS3 Rx Adaptor (sold separately), these goggles enable you to leave your glasses behind and easily snap the corrective vision insert directly into the goggle chamber. An articulating outrigger positioning system ensures a snug fit over your helmet and glasses, while a floating foam membrane eliminates eyeglass temple pressure for maximum comfort. An ultra-wide silicone-backed strap with QuickFit system and clip-buckle allows you to effortlessly adjust or remove your goggles. Store your goggles in the included microfiber bag when you aren't wearing them. Like all Smith Optics products, the Knowledge OTGs are made in the USA.