8×42 Waterproof Binoculars — BAK-4 Prism, 8mm Exit Pupil, Multi-Coated Optics

Eight-power magnification meets serious optical engineering in a daypack-ready package that pulls double duty from forest canopy to midnight sky.

The 8×42 configuration is the physicist's choice for versatility: the 42mm objective collects enough light for twilight birding and wide-field stellar views, while the 8× magnification keeps the field of view broad enough to track fast-moving subjects without a tripod. BAK-4 prism glass and fully multi-coated optics maximize transmission across the visible spectrum, delivering crisp, high-contrast images from 450 nm blue to 700 nm red.

• 8× magnification, 42mm objective diameter — 5.25mm exit pupil
• BAK-4 phase-corrected roof prisms, fully multi-coated lenses
• IPX7 waterproof & nitrogen-purged fog-proof body
• 367 ft / 1000 yd field of view — center focus wheel with diopter

Every purchase directly funds independent physics research at the Golden Physics Project.