... HAL, Immersion gold, OSP, Immersion tin, Immersion silver, etc. Other Technology: Gold finger, peelable mask, Non-across blind ... /buried vias, characteristic impedance control, Rigid-flex board etc. Reliability Test: flying probe test/fixture test, impedance test ... hole resistance test, and micor metallographic section analysis, etc. Wrap and twist: ≤0.7% Flammability: 94V-0 PCB for Mobile phone