SJK, founded 1989 Shenzhen in China 1989, is a professional manufacturer and exporter of electronic components including crystal filter, ceramic resonators, Ceramic Filter, Saw Resonator and SAW Filters. Products are wildly applied in Bluetooth, computer, computer peripheral, mobile phone, GPS system, wireless LAN & other precise electronic devices. The company has gained ISO9001 Quality Management System Certificate and ISO 14001 Environmental Management System Certificate.