... , HASL, Impedance Controlled, Vias Plugged with Solder Mask. 4-Layer PCB,Gold Finger,Red Solder Mask,HASL,Impedance Controlled,Vias Plugged ... Inspection (including warp & twist check) Dimensional Inspection (finished hole sizes, pcb profiles, etc) MicrosectionSolderability Test (245±5ºC; 3-5 sec ... , Carbon PrintingMaterialFR4, ROGERS, Taconic, ARLON, BT, Ceramic, Aluminum 4-Layer PCB with Gold Finger