As the title says, it's Iranian, and we don't know what to call it. Pretty standard striker release design, mostly plastic with steel balls imbeded in a plastic matrix for frag.
Oddly, this grenade comes filled with plastic (or plasticized) explosive (which is odd in that there is no need for plasticized explosive in a grenade, and as such most are filled with flake, powder, cast or pressed explosive). At least they don't come apart when you throw them. Easy to inert, too.
I find the embossed writing on the side especially cool; perhaps if someone took the time to translate it, it would not be known as 'model unknown'. Maybe it says 'if you can read this, infidel.... '
Edited to add: Motorcityman knew someone who could translate the writing, and took the time to do so (Thanks!). I believe the translator viewed the pictures in the opposite order, refering to the second picture first.
Direct from the translator:
In the first picture, the writing seems to be a serial number, for it is a mixture of letters and numbers. If we transliterate the letters, it will read as follows: SAL43LO59.
In the second picture, the writing can be read as "Sasid," "Sasad" or Sasud" - because the Arabic script does not usually write the short vowels - a, i or u. I do not know what its meaning is.
So there we have it...

