... 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 ... and ODM service are welcome.-We also welcome any quantity prototype orders as well as trial orders.-If possible ,please ...