wireless doorbell with optical signaling

Way of transferring wireless bells button reach 100 m number of melodies 32 way of pairing automatic pairing - self-learning special night light function optical signaling on bell yes optical signaling on button no maximum ring volume of 85 dB possibility to add another button yes, max 4 number of buttons in the package 1 pc additional (spare) button no waterproof button yes power button 1 × 12 V A23 (included) number of receivers in a package 1 pc volume control yes, 4 levels tr