One replacement Nikon Right Eyecup identical to that which was originally supplied by Nikon with the Travelite III & IV Series 7x20, 8x23, 9x25 & 10x25 Binoculars. This model only fits the side of the binocular which you use to observe with your right eye. You will need the corresponding left side eyecup to replace a pair of eyecups for the binocular, of course.