Need an extra lens or two? Oakley's got you covered here with several options to choose from for your Flight Tracker L goggles.
High Definition Optics® - High Definition Optics® (HDO®) is a collection of patented technologies that allow Oakley eyewear to meet or exceed the testing standards of the American National Standards Institute for optical clarity, visual fidelity, and impact resistance.
Prizm™ - Prizm lenses have been engineered to help you perform over a wider range of lighting conditions, reducing the need to switch lenses as lighting conditions change. You'll notice when looking at the lens tints that each Prizm lens offers appropriate variable light transmission across a much broader range than a traditional lens. This is the future, three lenses are all you need for any condition conceivable, and thanks to the broad range of coverage you can typically get away with just one.