... capability:1.Layer: 2-22 layer2.Product type: Rigid PCB,High Density Inverter PCB,thick copper PCB3.Materials: FR-4, CEM-3 ... .13mm21.Surface coating: Lead Free HAL, HAL, Flash Gold, Immersion Gold, Immersion Tin, Immersion Silver, OSP, Gold Finger Plating, Carbon Ink Printing, Peelable Blue Mask-We ...