... mm3) Min. Hole size: 0.01mm 4) Thickness tolerance: A) Single sided: 0.005" B) Double sided: 0.010" 5) Base ... materials: Polyimide and polyester 6) Conductor (copper thickness): 13um~105um. (RA and ED copper) 7) Cover-layer: Polyimide and polyester (solder mask printing ... ,OSP PREFESSIONAL SUPPLY fpc flex pcb,fpc flexible circuit,multi-layer fpc,multi layer pcb, single side fpc,fpc flexible,fpc desigm