Arm, part arm and disarm your system from this keypad. Programmable 4 digit pin number. Compatible with all AEI security wire free alarms (NOTE: won't part arm 5850 control panels). Single battery operation - no cables required. Discreet touch sensitive keypad. New 434MHz version. This accessory is NOT compatible with any 418MHz AEI alarm (including ALL alarms purchased before July 2004).