... Rigao ElectronicsShenzhen 1-22 layer FR4 PCB board and Aluminum PCB with RoHS and UL certificate - Contract Manufacturing- Engineering Services ... SilkscreenColorWhite,black,yellow,red,blue,greenMin. Size0.006”(0.15mm)Surface FinishHASL,HASL pb free,immersion gold,immersion silver, ... OSP,Gold Finger Palting,Selective thick gold plating, immersion silver,immersion tin, Carbon ink,peelable mask 3). Solder ...