What´s this fin on that Kazakh fulcrum???

Hi guys…

reviewing my archives, I ran into with these pics… of Kazakhstani Fulcrums ( BTW I got´em here 😀 )…

well, I wonder what´s this strange fin that is in those MiGs between the stabilizator and the wing? and which Fulcrum version are those??

Is it any modification peculiar to Kazakhstan??

Any answer will be welcomed!!!

TIA.
Alberto.-