Pitch: 1 mod: 3.14mm; 1.5mod: 4.71mm; 2mod: 6.28mm; 2.5 mod: 7.85mm; 3 mod: 9.42mm. Ratio: 1: 1 or 1: 2(1: 1 bevel gears can only be used exclusively, and cannot be mixed with 1: 2 or other modulus gears).
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