The JR Series 8x42mm Full Sized Waterproof Binocular, Green is a roof prism binocular. These binoculars feature BAK-4 prisms and fully multi-coated optics for crisp, clear viewing. Large 42mm objective lenses gather plenty of light to ensure the viewing image is bright even in low light conditions. The JR-842, 8x42mm binoculars are O-ring sealed and nitrogen purged making them waterproof and fogproof. Large focus wheel turns smoothly for precise focus adjustments. Independent right diopter adjustment makes it possible to adjust the focus to allow for strength differences in each eye. The JR Series binoculars are the ideal choice for hunting, birding, hiking or fishing.