The DDTO-1-30B from Shanghai Huaxiang Computer Communication Engineering is a Dual Directional Coupler with Coupling 30 dB, Coupling Variation 1.2 dB, Frequency 1 to 500 MHz, Average Power 100 W, Insertion Loss 1 dB. Tags: Module with Connectors. More details for DDTO-1-30B can be seen below.