The Piezo I wireless doorbell set is a Baseline by HEIDEMANN product. It includes a waterproof transmitter (IP55) with a nameplate, which is protected against water jets. The transmitter is self-sufficient and therefore does not require a battery. The receiver has the option to stay lit continuously. An optical call signal appears alongside the melody, displayed in a glowing blue ring. The volume of the gong can be adjusted in 4 different levels, with the highest level reaching 85 dB(A). The receiver can play 58 different melodies. Thanks to the plug-in connection, the gong only requires a power outlet.