You are bidding on a VERY NICE example of a 100% ORIGINAL WW2 United States Army M6 Periscope Head!  This was used in almost all Tanks, Tank Destroyers, and Armoured Vehicles that utilized an M6 periscope for vision.

Made of glass, brass, and steel, this item is in EXCELLENT used condition!  There are some slight marks, scratches, and wear, but it is still VERY SOLID otherwise and retains 95% original finish! The glass is still VERY CLEAR. I have indicated its location in the last photo.  Would make a PERFECT addition to any collection or display!