... Short lead time. 3. OEM pcba,SMT,DIP and final Assembly. High Standard SMT 4 layers PCBA manufacturingDetails for your check: ... mask color: green, black, blue, white, yellow, purple, and matt, etc.Solder mask hardness: 6HLegend/Silk screen Color: white ... test, hole resistance test, and micro metallographic section analysis, etc.Wrap and twist: ≤0Flammability: 94V-0 High Standard SMT PCBA manufacturing