Designed for the nature enthusiast who wants to pack light without sacrificing image quality, the Pentax 8x25 /10x25 /A-Series AD WP Compact Binocular delivers bright, clear images while weighing in at just 10.6 ounces. Their BAK4 roof prisms are phase corrected to improve image contrast and enhance color rendition. All of the optics are anti-reflection and fully multi-coated to maximize light transmission, producing the brightest views possible.An asymmetrical hinge design enables the binocular to be folded up much smaller than typical center-hinged optics. In order to cut weight, the housing is made of corrosion- and impact-resistant fiberglass-reinforced polycarbonate polymer. The material is also temperature resistant, allowing for its use in extreme climates while reducing expansion and contraction that wide temperature swings can cause (and which can make the optical components move out of collimation over time). Its optical tubes are nitrogen filled and O-ring sealed, making them submersible to 3.3' as well as fogproof in all weather conditions.Designed for the nature-enthusiast who wants to pack light without sacrificing image quality, the Pentax 8x36 /10x36 A-Series AD WP Compact Binocular delivers bright clear images while weighing in at just 22.5 ounces. The BAK4 roof prisms are phase-corrected to improve image contrast and enhance color rendition. All of the optics are anti-reflection fully multicoated to maximize light transmission to produce the brightest views possible.In order to cut weight, the housing is made of corrosion and impact-resistant fibreglass reinforced polycarbonate polymer. The material is also temperature-resistant allowing for its use in extreme climates while reducing expansion and contraction wide temperature swings can cause which can make the optical components move out of collimation over time. Its optical tubes are nitrogen-filled and O-ring sealed so they can are submersible to 3.3', as well as fogproof in all weather conditions.Pentax's 9x28 /9x32 A-Series AD WP Binocular features an exciting transitional magnification that produces an enhanced viewing experience over a lower power without the visible hand-shake often associated with higher magnifications. The BAK4 roof prisms are phase-corrected to improve image contrast and enhance colour rendition. All of the optics are anti-reflection fully multicoated to maximise light transmission to produce the brightest views possible.To help cut weight, the housing is made of corrosion and impact-resistant fibreglass reinforced polycarbonate polymer. It is also temperature-resistant allowing for its use in extreme climates while reducing expansion and contraction wide temperature swings can cause which can make the optical components move out of collimation over time. Its optical tubes are nitrogen-filled and O-ring sealed so they can are submersible to 3.3', as well as fogproof in all weather conditions.Optical Performance- 8x 9x 10x magnification- BAK4 roof prisms- Phase-corrected prism coatings enhance contrast and improve colour rendition- Anti-reflection fully multi-coated opticsConstruction Details- Lightweight fibreglass-reinforced polycarbonate housing- Housing is corrosion, temperature, and impact resistant- Nitrogen filled for fogproof performance; submersible to 3.