The ATS1253 4-Door Controller is a versatile access control panel to extend the Advisor MASTER system with advanced access control functions. Real-time alarm and access control on 4 doors, with power supply and housing. A total of twelve 4-door controllers can be connected to a master advisor panel. To program the controllers, an LCD user interface must be included in the system. A total of twelve 4-door controllers can be connected to a master advisor panel. To program the controllers, an LCD user interface must be included in the system.