This Romanian PAR-1 is mostly made up of traditional AKM parts with a twist. It features a pump action mechanism rather than a functioning gas system.
Interestingly unlike most pump actions the pump on this rifle is spring loaded. Meaning that it will slide back forward after being pulled back and released.
This is mostly a guess, but I would imagine it’s probably for places like the UK where semi-auto rifles are caliber restricted to .22 rimfire. If you want to shoot anything larger the action has to be cycled manually.
I’ve seen pump-action conversion kits for the AR platform as well.