FPC Category Single-side Applied with single sided material to make pattern and cover the cover layer on it. Double-side Applied with double sided material to make pattern on both side then add on cover layer on each side . Single-side double access Applied with single sided material to make pattern but make some window on base film and add on cover layer on pattern top. The final products will have single layer copper but two side access possibility Mmi-layer Binding a single sided and a double sided FPC together or binding a double sided and a double sided FPC together. Rigid-flex board Binding flexible and rigid boards structure together in same units as one part