Features:
1.Made of brass, long time service.
2.0.5 modulus , 20 T wheel, 5mm bore gear shaft
3.Shaft Z1=1, turn a round of gear T, can get a large transmission ratio, generally in the power transmission, the transmission ratio I=10-80, like big transmission ratio, if use with gear transmission, will need to take the multi-stage transmission.

Specifications:
Material: Brass
Color: Yellow
Modulus: 0.5
Weight:15g

Size of wheel:
T:20
T Dia:11.2MM
Height:12MM/0.47 Inch
Outer Diameter:11MM/0.43 Inch
Hole Diameter:4MM/0.16 Inch
Step Size:9x7MM/0.35x0.27 Inch ( Dia x H)
Overall Size:12x11x4MM/0.47x0.39x0.12 Inch( H x OD x ID)

Size of gear shaft:
Height:20MM/0.79 Inch
Outer Diameter:9.7MM/0.38 Inch
Inner Diameter:5MM/0.2 Inch
Size:20x9.7x5MM/0.79x0.38x0.2 Inch( H x OD x ID)

Package include:
1 x wheel
1 x gear shaft
2 x screws