Designed to provide updated functionality & styling in home with existing intercom systems; Runs on existing wires; Replaces 3, 4 & 6 wire ; 30W RMS power drives up to 15 room stations & 3 door speakers; 30% smaller than previous models; 2 music source inputs & 8 AM/8 FM music station presets; Stereo upgrade path with optional power amp; Remote speaker volume & source control ; Intercom-only & door release features; White; 15.25 x 15.31;