Note:the drawing does not represent the real object, just show the parameters of the gear

Module 0.3 25 Teeth Plastic Gear, Interference Fit 1.0mm Shaft
Outer diameter 8.1mm, gear thickness 1mm, middle boss flat round type, round diameter 3mm, thickness 6.5mm

The bottom boss thickness is 1.5mm and 2.3mm in diameter

Weighs 0.1g