Double layer sound proof, Low noise.

双层隔音，噪音低。

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Hydraulic transmissions; Noise source; Disassembly test; Proof;

液力变速器；噪声源；分解试验；验证；

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Hydraulic transmissions; Noise source; Disassembly test; Proof;

液力变速器；噪声源；分解试验；验证；

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