The DDTO-1-40 from Shanghai Huaxiang Computer Communication Engineering is a Dual Directional Coupler with Coupling 40 dB, Coupling Variation 1.2 dB, Frequency 1 MHz to 1 GHz, Average Power 100 W, Insertion Loss 1 dB. Tags: Module with Connectors. More details for DDTO-1-40 can be seen below.