【Large circle modulus】: 0.2m. 【Small circle modulus】: 0.25m. 【Features】: 0.2 mold 40T-0.25 mold 9T-double layer copper gear (0.7 hole). This gear is very small, with a large ring of 0.2 module 40 teeth and a small ring of 0.25 module 9 teeth.
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