DESC: Add an additional button to expand your door chime system. The bead on the face of the button allows you to change tune quickly and easily. Additional button for side or back door No wiring necessary - installs in minutes Select sound on front of button Weather resistant Up to 150' range Scrolling bead on button changes tune quickly and easily 10 year button battery included Use indoors or outside from -30-degrees F to 130-degrees F 10 year warranty Works with chime series: RC3200, 3300,3400,3600,4000, and 3720