The 1851 from KRYTAR is a Directional Coupler with Frequency 500 MHz to 18.5 GHz, Coupling 10 dB, Coupling Variation ±1 dB, Frequency Sensitivity ±0.7 dB, Directivity 12 to 15 dB. Tags: Module with Connectors. More details for 1851 can be seen below.