The Piezo I wireless bell set is a Baseline by HEIDEMANN product. It includes a waterproof transmitter (IP55) with a nameplate that is protected against water jets. The transmitter is self-sufficient and therefore does not require a battery. The receiver offers the option to remain permanently lit. An optical call signal appears alongside the melody, displayed in the 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.