... surface finish: HAL, Flash gold, Immersion gold ·Colorful solder mask PCB ·PCB Bwith Bridge Connecting ·RoHSLayer Count1-22 layers ... 0.15mmMinimum Laser Hole0.075mmCopper Thickness17µm-175µmMini Solder Mask Bridge0.025mmImpedance Control Tolerance1.±5%Surface finishingHASL,LEAD- ... tin,Immersion Silver,Plated gold,OSP,Carbon ink.Solder Mask ColorGreen,Red,White,Yellow,Black,BlueQuality StandardsIPC-A- ...