FP11-A Floating-Point Processor
It consists of a single hex board, the M8267. Its connections to the KD11-EA include two over-the-top connectors; a 20-pin connector to the M8265 card of the KD11-EA, and a 10 pin connector to the M8266 card.
The latter over-the-top connector uses the connectors which normally hold the maintenance cables to the KY11-LB Programmer's Console; in systems with a KY11-LB, the cables to the console will now connect to the M8267 card. (This is all necessitated because the FP11-A needs access to signals carried over the maintenance cables.)