Rosslare Security AC-425-PCBA Professional Scalable IP Networked Access Controller - Two or Four-Door (4-Reader IN/OUT, IN/IN) topology, networked up to 1023 panels to one PC. Full online/offline operation. 30,000 Users, 20,000 event history. Compatible with MD-IO84 IO 8 Input / 4 Output IO Expander and MD-D04 Four Door Expander. Advanced event-action logic engine. Tamper protected, lockable metal enclosure, transformer, power supply/charger and Bell/Alarm/Chime sounder. System management performed on the AxTrax PC software platform with client/server operator access. Space for 7AH battery (Battery sold separately). NOTE: MD14 Converter cable is required (sold separately) for connecting to AxTrax PC software via RS485 serial link. No on-board IP, PCB only.