Thank you for viewing. Nikon FM Eyepiece Collection Diopter Correction +1.0 Comes with the valuable original box. This is used to correct the diopter when the viewfinder is difficult to see due to farsightedness or wearing reading glasses. You screw it into the viewfinder. Although it is for the FM, it can be used with models with the same viewfinder diameter, such as the FM2 and NewFM2. I think it is in good condition as it has only been tried on a few times, but please understand that it has been stored at home for a long time. Thank you. #Nikon #Nikon #FM #FM2 #NewFM2 #Eyepiece #DiopterCorrection #Viewfinder #Accessories #Camera