Four self-locating magnets assist in lightning-fast lens replacement while four snap pins keep the lens securely locked in place. meanwhile, the medium fit accommodates a wide range of face shapes while boasting an impressively wide exv field of view. the axis also includes two of the best lenses in the business, premium vivid lenses with optics by zeiss®. included is one sun/all-conditions lens and one infrared storm/low-light lens, so you're always ready when the conditions change.