IPC-6013E standard covers qualification and performance requirements for flexible printed boards designed to IPC-2221 and IPC-2223. The flexible printed board may be single-sided, double-sided, multilayer or rigid-flex multilayer. All of these constructions may include stiffeners, PTHs, microvias, and blind/buried vias. The IPC-6013E standard incorporates new and updated requirements for final finishes, rigid-to-flex transition zones, foreign inclusions, surface mount land anomalies, plated internal layers, dielectric removal as a function of wicking and etchback, copper filled via structures microvia structures.