Now there are Brass or Steel version to choose from.
Pinion gear found in the center axle of the new type 6x6 KM cars.
Selling as one(1) set of 4 pcs
You will need two(2) per center axle
Teeth - 14T
Gear outer diameter - 7.8mm
Shaft Outer diameter - 5.5mm
Shaft Inner Hole Diameter - 3mm
Height - 7mm
*all above approx