Gehmann Adjustable Iris Clips for ordinary glassesImproves depth of field vision for a clearer rearsight and foresight picture but allowing use of your own glasses for distanceThe iris is sprung-mounted on its plate to allow accurate positioning of the iris for quick and perfect alignmentIris has the latest surface coating to eliminate oxidation and to preserve the matt black anti-glare finishClips to your glasses with a spring loaded rubber clampCan be easily flipped up (and stays up) for normal vision- easy to wear- best qaulityContact us at 70822-33324, if the product is in pre-order status.