... /CEM-1/AluminiumLayersingle layer,double layer,multi-layer(4-10)Board Thickness0.3mm-3.0mm,+/-0.1mm(tolerance)Copper Thickness1/2OZ ... -3OZ (35um to 105um),+/-8um(tolerance),purity 99.5%Impedance Control±10%Bow and Twist MAX.0.75 ... ,ISO,ROHS,UL, Welcome to visit WALBOND ! Multilayer dvr PCB board