The DEC MF11 was a magnetic core memory module primarily used as main memory in various Digital Equipment Corporation (DEC) minicomputers, including early PDP-11 and PDP-8/E series. Each MF11 unit typically provided 8K words of 18-bit memory (16 data bits plus 2 parity bits) or could be configured for 16K words. It was a standard, expandable memory component for these systems.