No. 121.5A
Modulus: 0.5
Number of teeth: 12
Applicable shaft / aperture: 1.5mm (tight)
Diameter: 7 mm
Thickness: 5mm

How to calculate the outer diameter of gear : 
Gear Diameter = (number of teeth + 2) * Modulus
For example(0.5Modulus, 10T): Gear diameter= (10+2)*0.5=6mm
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How to calculate the modulus of gear : 
Modulus= Gear Diameter/(number of teeth + 2)
For example(6mm Outer Diameter, 10T): Modulus= 6/(10+2)=0.5

Material: Plastic

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