VKEL1003 Features: * Loud ringer * Easy to install * There are 4 different ringing sounds to choose * A second set of contact inputs will trigger a door chime (doorbell) sound * Used to notify that a door has opened, used as a door bell, push for assistance button * Used by employees that often work away from their desks, allowing them to instantly recognize when their phone is ringing * Generate loud ringing from an analog ringing line or from a dry contact closure Includes: * Includes power supply and connections for an optional external speaker Dimensions: * Overall dimensions: 5.5" H x 4.5" W x 1.6" D