The Nokia 31's 50-pin M2M System Connector is connected to the application module with a flat cable connector (e.g. Samtec FFSD-25-D-X-01, X = cable length in inches). The flat cable is connected to a pin header connector on the customer application (e.g. Samtec FTSH-125-01-L-DV-K-P-TR). A board-to-board connector that is connected directly to the M2M system connector of the Nokia 31 can also be used in the customer application.