... Solder Mask, Vias Plugged with Solder Mask, RoHS Compliance. 2-Layer PCB,Gold Finger,Blue Solder Mask,Vias Plugged with Solder Mask ... (including warp & twist check) Dimensional Inspection (finished hole sizes, pcb profiles, etc) MicrosectionSolderability Test (245±5ºC; 3-5 sec ... Peelable Mask, Carbon PrintingMaterialFR4, ROGERS, Taconic, ARLON, BT, Ceramic, Aluminum 2-Layer PCB with Gold Finger