Russian T-54 tank, used by Finland.  This model was cut open in for training purposes. Various systems of the tank have been illustrated with different colors.
<p>This view shows the commander's periscope mounted under the observation cupola. 
</p>
Finnish Tank Museum (Panssarimuseo) in Parola.
<a href="//commons.wikimedia.org/wiki/User:Balcer~commonswiki" title="User:Balcer~commonswiki">Balcer~commonswiki</a>
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<span class="int-own-work" lang="en">Own work</span>