Apartment Door Access Bell Panel with Child Mifare Proximity Card Reader, Flash Memory Download by USB to Secure software, Door Relay for Lock Control, Built in Logic Control Module (Time Clock), Back Lit, Bell Push, Functions: (Child DND indicator), Online update. Disable Bell Enable Light Flashing if DND/Child is active. Bus Enabled Network. Secure, Screw less Fixing Magnet Technology, Include 1Z for Door Magnet, No Need for Special Back box (Uses standard 3x3)