DK Photonics offer optical passive components for fiber laser and,fiber sensor, and fiber telecommunication applications,such as high power isolator,pump combiner,1064nm Bandpass Filter,(6+1)X1 Pump and Signal Combiner,PM Circulator,PM Isolator,pm Coupler http://www.dkphotonics.com/ 4F, Building 18, Qinghu Industrial Park, Dahe Road, Longhua Dis., Shenzhen, China 518109