These are really cool and can be and WERE used as periscopes in some conflicts. During the Iran/Iraq war in the 80s these were commonly sent as aid and used by forces as a straight-up periscope, as well as a spotting device for certain artillery pieces. I was only able to get a few of these a couple years back, and kept this one, but figured it's time to pass it on to someone who will enjoy it more. These are not really easy to find, especially in as good of shape as this one is. Glass is super clear.
