1.printed circuit board pcb 2.16layers with immersion gold 3.1.6mm printed circuit board pcb 4.UL ... (lead freecompatible),Carbon ink,Peelable S/M,HASL(lead free),Immersion silver/tin,Gold finger plating,ENIG+gold finger plating ... ,Immersion Silver+gold finger platingProduction typeHigh precision multi-layer board,Blind ...