... .005 mm 3.Excellent design and engineering 4.Reliable quality and competitive price Copper contact spring ... , Silkscreen, Heat treatment, Black oxid.EngineerExperienced technicians and professional engineersProcessProgression die, Deep drawing, Grinding, Stretch, ... Punch, Bending, Surface treatment and Assembly, QC and packingDesignMould design according to your drawingAdvantageStrict quality ...