MRC:
Those unusual or unique characteristics or qualities of an item not covered in the other requirements and which are determined to be essential for identification.FEAT
Special Features:
C/o circuit card assemblies; cables; carrying case; receptacles; on-off controls; status indicators and lamps; powered by aircraft power for both operation and self test modes; provides test stimuli, self test capability, signal generation and measurement, switching, bus interfacing, clock generation and receipt of manual controls via the integrated keyboard