*A speakerphone combines a microphone and loudspeaker in a single device, enabling Everybody over a contact to talk and hear clearly while not having to make use of a headset or keep a telephone.?? b?o v? quy?n riêng t? và b?o m?t c?a các cu?c h?p, Yealink SmartVision 40 ???c thi?t k? v?i n?p b?o m?t ?ng kính t? ??ng, mang ??n cho ng??i dùng t