Bells, gongs and the like, non-electric, of base metal; statuettes and other ornaments, of base metal; photograph, picture or similar frames, of base metal; mirrors of base metal.
非电动的贱金属铃、钟、锣及类似品；贱金属雕塑像及其他装饰品；贱金属相框或画框及类似框架；贱金属镜子。
The prior various crossing adopt electric bells or ordinary transistor audible devices, and have the problems of difficult volume adjustment, large noise disturbance, etc.
目前各类道口采用的电铃及一般晶体管音响装置，存在着音量不易调整，噪音干扰大等问题。
The prior various crossing adopt electric bells or ordinary transistor audible devices, and have the problems of difficult volume adjustment, large noise disturbance, etc.
目前各类道口采用的电铃及一般晶体管音响装置，存在着音量不易调整，噪音干扰大等问题。
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