With a 95% light transmission, the Poseidon Series has the highest brightness available in any Fujinon binocular. The ability to transmit so much light is due to Fujinon's patented Electron Beam Coatings on each and every optic. Every binocular in the Poseidon Series is not only built to US Military specifications, but also has waterproofed and sealed light alloy housings, which are filled with dry nitrogen, is tripod mountable, and is available with a compass in the 7x50 model. To top this off, Fujinon offers a lifetime limited warranty.