Attaches to the viewfinder eyepiece minimizing extraneous light and vision fatigue. DK-17 Viewfinder + DK-19 Round Eyepiece + EN-DK19 Eye Cup 3 in 1 Set. 1pc x Eyepiece Set 3 in 1 for DK-17,DK-19. DK-19 for for Nikon D5,D500,D810A,D810,D4S,Df,D4,D2 Series,D3 Series etc.
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