The Fanuc A20B-2902-0080 is a combined memory module designed for Fanuc Series 16/18 Model B and compatible CNC systems. It integrates 4MB FROM (Flash ROM) for non-volatile storage of system software, part programs, and parameters with 512K battery-backed SRAM for real-time data retention and machining information during power loss. This plug-in daughter PCB features industrial-grade memory chips, robust edge connectors for direct motherboard integration, and low-power CMOS circuitry operating on system-supplied voltages. [stock available]