Orion 10151 10x50 E-Series Waterproof Astronomy Binoculars (Black) A great 10x50 binocular for both beginning and experienced amateur astronomers alike Big, 50mm lenses and 10-power magnification work together to provide wonderful views - day or night Waterproof construction for worry-free use in almost any weather Multi-coated optics and BAK-4 porro prisms deliver a bright, clear 6.5 degree field-of-view 19mm eye relief for comfortable views