This is a new RG-830 73mm Diameter x 4mm 850 nm Near-Infrared Thick Long Pass IR Glass Filter .
This specifically came from Xenonics and was made to be used with the NH1-150 NightHunter and is a standard issue for US Army BCT Sets and USMC EOF Mission Modules.
It provides covert infrared, visible light.

Which means the optics are good quality, although we don’t have any other additional specs.

The box is stamped “RG830”