... hours4 layer sample in 72 hoursAdvanced technology productsMass production for heat conductivity 4.0w/m °C Alum PCB PCB TechnologyLayer ... (550x640mm)Impedance control: ±10%Surface finish: OSP, HAL, HAL lead free, electronic gold, ENIG, gold finger, immersion silver, immersion tin, thick ... material: FR4 (Shengyi, KB, Intl.); High TG (TG150, TG170), Halogen free, Alum. ( ) Cu, Iron, ceramic base