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Hearing protectors - Safety requirements and testing - Part 5: active noise reduction ear-muffs.
听力保护器。安全要求和试验。第5部分：有源降噪耳罩。
youdao
-
Hearing protectors - Safety requirements and testing - Part 5: active noise reduction ear-muffs.
听力保护器。安全要求和试验。第5部分：有源降噪耳罩。
youdao