I don't know the official Belgian name for this grenade. The name above is the German designation during ww2.
Same grenade was also used in

The body was made of thin aluminium. The grenade could be fired from a rifle as well with the use of a cup discharger.

Total length: 120mm, Body length: 95mm. Diameter: 40mm.
Total weight: 265gram, Filling: 180gram TNT.
Delay: 4.5seconds.