The Fanuc A20B-2902-0237 is a compact additional SRAM memory module designed for Fanuc Series 16/18/21 and compatible CNC systems. It provides 256K bytes of battery-backed SRAM for expanded program storage, parameter retention, and machining data backup during power loss. This plug-in daughter PCB features industrial-grade CMOS memory chips, robust edge connectors for direct motherboard integration, and low-power operation on system-supplied voltages. Parameters and programs typically require reloading or verification after installation. [stock available]