Unimog.
To grease the bearing you have to remove it from the shaft, this a simple job. The regrease tool consists of a plastic disc which is a press fit in the ID of the bearing it has a small sholder to stop it going right through. Also a steel disc shaped like a large welsh plug, the flange on this disc is the diameter of the part of the bearing outer that you can see. The metal disc has a screw in the centre that screws into the plastic disc. The metal disc is screwed onto the oposite side of the plastic from the sholder. there is a grease niple in the metal disc. When grease is pumped in it fills the space between the discs and then is forced through the bearing, Eric