Aiming circle (?)

[Grubhy]

Hello,

recently I bought this unknown item. It is Russian period made (1943) and come with genuine issued hessian cover. I assume that is sort of aiming circle in simplified version. Please let my know your thoughts.

[Grubhy]

In my opinion that works similar to compass:

[Grubhy]

Please note bakelite handle on the bottom which helps to keep aiming circle (? ;-) ) in hands. Markings on the next pics.

[Grubhy]

Made in March 1943, next white painted stamp is less luminous for me. Hope you can help. Have a good day