... This form is of my company's process capacity for your reference, for more messages, pls contact with us freely!ItemSpecification MaterialFR ... CEM-1/AluminiumLayersingle layer,double layer,multi-layer(4-10)Board Thickness0.3mm-3.0mm,+/-0.1mm(tolerance)Copper Thickness1/ ... % pass for the first time,+/-2%(tolerance) Certificate SGS,ISO,ROHS,UL, Welcome to visit WALBOND ! 4 Layer PCB for dvd decoder board