PS31-3WHPT, Night Vision Goggle - USA Gen 3, White Phospher, High-Performance, Auto-Gated/Thin-Filmed, 64-72 lp/mm, A-Grade. The PS-31 Binocular Night Vision Device (BNVD) is a compact, lightweight, dual tube goggle to replace the legacy PS-15. In a sea of dual tube night vision goggles, the PS-31 is one of the smallest and lightest units by far. The PS31s can be outfitted with various levels of high-performance US made Gen 3 image intensifier tubes. Operators input, the PS-31 was designed to increase system resolution, significantly reduce head borne weight, improve system of center ...