Among the world's greatest binoculars for boating or astronomy applications, the military-specification Fujinon 7x50 FMTR-SX Polaris Binocular transmits an incredible >95% of the light reaching the binocular and has Fujinon's EBC multi-coatings on every optical surface. It is also equipped (as is any Fujinon Polaris series binocular) with flat-field, distortion-free eyepieces that accept optional filters. The 100% fog and waterproof 7x50 Polaris withstands drastic temperature and humidity changes with ease, has abundant eye relief for use with sunglasses in bright conditions, and is simply the brightest, highest-resolution 7x50 boating binocular money can buy. 
 
Fujinon's best military-specification 7x50 Porro prism binocular with a 7.5° angle of view
Nitrogen-purged water and fogproof lenses
Up to 13 Fujinon EBC multi-coatings on all optical surfaces
56-74mm interpupillary adjustment range (HUGE!)
Thick and protective rubber armor on an all-metal housing
Accepts optional eyepiece filters
Ideal for both boating and astronomy applications
Peel-down-style rubber eyecups
Extremely long 23mm eye relief