The DDTO-2-40A from Shanghai Huaxiang Computer Communication Engineering is a Dual Directional Coupler with Coupling 40 dB, Coupling Variation 1.25 dB, Frequency 800 MHz to 2.2 GHz, Average Power 500 W, Insertion Loss 0.3 dB. Tags: Module with Connectors. More details for DDTO-2-40A can be seen below.