Keri Tiger II PlatformKeri?s PXL-500 Tiger II Controller is an RS-485 based hardware platform with a loyal following and years of proven reliability.Provides sophisticated access control solutions for up to 256 doors at a single site and thousands of doors spread over a number of remote sites. Its companion SB-593 Satellite Expansion Board simply takes flexibility and expandability one step further. The system is managed by Keri?s Doors32 software or Doors.NET software, with Doors.NET being recommended for all new installations.RS-232 serial port for direct connection to PC or via TCP/IP or modem for remote site management100% intelligence at each doorExpandable by 1 or 2 doors at a timeUser Capacity: 65,000RS-485 Controller Network for up to 256 doors per site