... reference. DescriptionDetails SpecificationBase MaterialFR-4,Aluminium-backed board,Halogen-free,Lead-free compatible,High Tg ... clearance0.045mm0.03mmImpedance tolerance±10%±8%Finished board thickness0.25mm-3.5mm0.20mm-4. ... finger plating,ENIG+gold finger plating,Immersion Silver+gold finger platingProduction typeHigh precision multi-layer board,Blind hole board, Buyerd hole board,High frequency board ...