... Controlled, Vias Plugged with Solder Mask, RoHS Compliance. 6-Layer PCB,Gold Finger,Black Solder Mask,ENIG,Impedance Controlled,Vias Plugged ... (including warp & twist check) Dimensional Inspection (finished hole sizes, pcb profiles, etc) MicrosectionSolderability Test (245±5ºC; 3-5 sec ... Mask, Carbon PrintingMaterialFR4, ROGERS, Taconic, ARLON, BT, Ceramic, Aluminum 6-Layer PCB with Gold Finger