Slim profile mini wireless doorbell,does not interfere with other socket positions when inserted into the socket. 4 Call Buttons + 3 Wireless Musical Doorbell Receivers for Home Elderly Shop Call Black 1 set includes: 4 call buttons+3 indoor music ringtone receivers +4 adhesive blocks+4 12V23A batteries+4 prompt stickers+1 screwdriver+1 instruction manual.
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