The left side of this binocular reads "7 X 50". It has individual eye focus with coated lenses. The right side reads "U.S. marine corps/mark 46. No. 6057, 1944" and :Bausch & Lomb/Opt. Co./ Rochester/N.Y. USA." A reticule is fitted in the left ocular . This model was made exclusively for the U.S.M.C. in 1944. Total production of marine corps marked binoculars is thought to be only 10 to 15,000 pair.
WWII issue polarizing filter set for US Naval Binoculars. Marked "BU. SHIPS, USN V.D. FILTER" Beck-Lee Corp Chicago, USA Pats. Pend." This clip on style polarizer was meant to darken the flash of ship cannons, rocket jets and other bright "flashes" that might get in the way during viewing. I've been told this type of polarizer was used during atomic testing.... Slide levers to opereate polarizers.