max. range 150 meters Variable loudness between 70 and 90 dB(A) Choice of 8 melodies Wall fastening Optical call signal (3x blue LED) can switch between LED / Tone / LED + Tone Weatherproof sender IP55 with name plate and LED (incl. 1x CR2032 3V battery) Receiver batteries not include: (2x 1,5 Volt LR6 / Mignon) Choice of 256 radio frequencies Compatible to all HX-devices