The FMC424 is a dual port QFSP+ FMC and is electrically and mechanically compliant to FMC standard (ANSI/VITA 57.1) except the FMC’s component height. The height of the QSFP+ modules is 5 mm higher than the maximum component height of 4.7mm (inside the component envelope) that is specified in the FMC standard. The standard FMC424 is equipped with an FMC connector that features the standard stacking height of 10 mm. If a standard FMC424 is to be placed on a carrier board, the carrier board cannot have any components or exposed copper in the component envelope defined in ANSI/VITA 57.1