Polish prototype battle rifle: "Karabin samopowtarzalny wz. 1921 (kbsp wz. 1921)<br>
Drawing made on the basis of low quality illustration. The drawing may not include construction details
<a href="//commons.wikimedia.org/wiki/User:Sumek101" title="User:Sumek101">Sumek101</a>
CC BY-SA 4.0
<span class="int-own-work" lang="en">Own work</span>