... 4, multi-layer pcb,Detailed technical requirements:layer:6material:FR4(SY)Board thickness: 1.0mmSurface finish:immersion goldMin through ... No ItemsCraft Ability 1Surface FinishHASL,Immersion Gold,Flash Gold,Gold Plating,OSP,Immersion Tin etc.2Layers2-30 layers3Minimum Line ... board,single board,double-sided board,multi-layer board.Hasl board,immersion gold,immersion silver,plating gold.we sincerely hope ...