This is TECKNET double bell Wireless Doorbell, Doorbell IP65 Waterproof Twin Wall Plug-in Cordless Door Chime Kit with 400m Range, 60 Chimes, 120dB Lound 5-Level Volume & Blue Light, Plug in Door Entry Bell TeckNet Wireless Doorbell:The Plug-in Wireless Door Bells and Push Button makes it easy to replace your home's generic doorbell ring with a chime tune. with two transmitter
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