Key switch: reset ＊ 1, doorbell button ＊ 1. Microphone: full duplex, sensitivity: ≥ - 38 ± 3dBm. Antenna: 3DBI 1433 Ant 1. Input interface: TF Card 1, Micro USB 1, Mic 1, PIR 1. Speaker: built-in 8 Ω/1W.
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