The 317.2021-30/S from Microwave Devices Inc. is a Directional Coupler with Frequency 500 MHz to 1 GHz, Coupling 30±1.25 dB, Coupling Variation ±1.25 dB, Frequency Sensitivity ±0.75 dB, Directivity 25 dB. Tags: Module with Connectors. More details for 317.2021-30/S can be seen below.