These grenades are basically used as riflegrenades, but can be easily converted into handgrenades by taking off the fin-assembly.
Both grenade body and tail are made of green plastic.
Markings on the safetylever are in yellow.

As a grenade:
Length: 151mm , diameter: 40mm.
Weight: 277gram including 71gram TNT.
With the fragmentation sleeve attached the grenade weighs 568gram.

PRB103 as rifle grenade: weight: 682gram.
PRB104 as rifle grenade: weight: 795gram.