... PCBADetailed Product Description PCB Assembly, Gold finger board 1) Layer: 6 layer2) Board finished thickness: 1.6mm3) Material: FR-44 ... tolerance:±3milTolerance of etching:±1milSolder mask registration tolerance: ±2milFinished board : Thickness<=1.0mm: +/-0.1mm Thickness>0. ... Blue,Red, White and so onSurface freatmentHASL,HASL Lead Free,OSP ,Immersion Gold, Immersion Ti, Immersion Sliver, Flash gold ...