17 appealing polyphonic melodies (2-/3-tone, Westminster, pop, classical, special call sequence for the hearing impaired, etc.) and a mute function with LED control. Alarm function with DIN emergency tone for special situations. User-friendly selection of melodies and 500mJ flash. 4-position slide switch for setting the ringing signal (1 melody/flash, 2 melody only, 3 flash only, 4 silent). Stepless volume control. Waterproof combo radio push button with nameplate and LED transmission control. 13 call differentiations for optimal access control. Central call: multiple receivers can be controlled by one transmitter. Individual call: each receiver can be individually controlled by additional transmitters. Matrix call: combination of central and individual call possible. Receivers/transmitters pre-programmed at the factory. Easy integration of additional transmitters at the push of a button.