4-Layer PCB with Gold Finger, Red Solder Mask, HASL, Impedance Controlled, Vias Plugged with Solder Mask. 4-Layer PCB,Gold Finger,Red Solder Mask,HASL,Impedance Controlled,Vias Plugged with Solder Mask. CertificatesULISO9001TS16949ISO14001--------------------------------------------------------------------------------Testing Items100% Electrical Test 100% Visual Inspection (including warp & twist ...