Special thanks to Soheil jan.
Here is a summery of different generations(or versions) of Shahed 129:
The first generation was the first prototype which was first seen in 2012, it had fixed landing gear and a more somple FLIR
The second generation was seen in 2013, it had retractable gears and featured a more advanced FLIR.
The third generation which is the mass produced one has a lighter FLIR and has a different nose compartment which allows it to be upgraded with SATCOM
The fourth generation is the one seen today, it will be equipped with SATCOM, SAR radar and improved engine.
1st, 2nd and 4th illustrated by dear Salman
The third generation with a different nose compartment
Third generation design allows it to be
upgraded with SATCOM and SAR radar
Iranian SAR radar which was seen for the first time in October 2015.