Kingtronics are ISO, UL, SGS certified manufacturer since 1990 with two big factories.
ISO 9001:2008 certification
http://www.kingtronics.com/pdf/iso.pdf
Bridge rectifier UL certification
http://www.kingtronics.com/pdf/Bridge-rectifier1.pdf
Trimming potentiometer SGS certification
http://www.kingtronics.com/pdf/Trimming-potentiometer1.pdf
Dipped tantalum capacitors SGS certification
http://www.kingtronics.com/pdf/Dipped-tantalum1.pdf