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增音话机德国市场上推出了专为老年人设计的增音话机,这种话机可以自由调节音量,特别适合听力有不同程度衰退的老年人使用。防暴手杖日本研制生产
Add-on phone Germany introduced on the market designed specifically for the elderly add-on phone, this phone can freely adjust the volume, especially for hearing the elderly have varying degrees of decline in use. Riot Cane Japan to develop and produce