This Medical Rigid-Flex FPC illustrates how designers use flex to reduce board thickness as well as package size and weight, and incorporate connectors into the bare board design.

Application: Wearable Insulin Pump
Size: 3 by 3
Layers: 6 Overall, 2 Flex
Materials: Adhesiveless Flex, Polyimide Core, Polyimide No-Flow Prepreg
Traces: 4/4 Innerlayers - 4/4 Outerlayers
Minimum Hole: 0.010
Minimum Pad: 0.022
Thickness: 0.030