FCI Basics Compact PCI Millipacs? 2mm hard metric (HM) connectors are designed in accordance with IEC 61076-4-101 and fulfill the interconnection requirement of the Compact PCI bus architecture. Millipacs? range currently supports 10Gb/s and 25Gb/s data rate with backward mating compatibility to the standard 2mm HM IEC 61076-4-101 connectors.