Orion 9544 10x50 Resolux Waterproof Astronomy Binoculars These rugged 10-power binoculars boast high-resolution, flat-field optics Ideal binoculars for scanning the starry skies, or for daytime terrestrial use viewing birds, wildlife, and scenery Fully waterproof and nitrogen purged to prevent lens fogging when using in damp environs 50mm objective lenses provide bright views across a wide 6.5-degree field of view High-quality BAK-4 prisms and advanced multi-coatings on all optical surfaces provide maximum light throughput for bright views rich in contrast