The DDTO-1.6-40 from Shanghai Huaxiang Computer Communication Engineering is a Dual Directional Coupler with Coupling 40 dB, Frequency 1.667 to 1.683 GHz, Average Power 50 W, Insertion Loss 0.3 dB, Directivity 18 dB. Tags: Module with Connectors. More details for DDTO-1.6-40 can be seen below.