Born from WW2, these vision blocks are scarce today. The housing is with a 'reddish mottled bakelite' type structure and the ballistic glass was made by SOVIS, a premier French glass maker that was eventually purchased by Corning in the U.S. Roughly 7.5" long and 4.25" wide with an extended width shoulder and thick rubber gasket 2/3rds the way down the body. Optics are relatively clear and would be termed a 'Periscope'. Military designation is APX L794B . While some have said that these periscopes were from WW2, we cannot be sure, but suspect they may be linked to vehicles like the post war AMX 13 tank etc.
