Say goodbye to sun glare as the sun rises on your early morning hunt.The functionality of the FlashShield is three-fold:1) Kill flash function: Blocks reflections off the lenses that may otherwise expose your position to your target.2) Sunshade function: Helps reduce glare, easier to see objects in bright light conditions.3) Lens Protection function: Helps keep dust/particles from easily getting directly to lens.The FlashShield easily clips-on to most full-size binoculars and riflescopes (32mm-43mm).