My best guess is that this grenade was probably manufactured in some local factory , but maybe someone knows more about this Partisan grenade.
Josip added the name "Patizanka-Jajce 1943", Jajce is a town in Central Bosnia.
The fuze is again similar to those found on most WW2 grenades.
It carries the same marking on top as the unknown grenades on the previous page.

Length: 105mm , diameter: 46mm.
Filling: 47gram TNT
4-5seconds delay fuze.

Photos and info © Josip.