The QMC-CRYOCOUPLER-20 from Quantum Microwave is a Directional Coupler with Frequency 4 to 12 GHz, Coupling 20 dB, Directivity 15 to 20 dB, Insertion Loss 0.5 to 0.75 dB, Return Loss 15 dB. Tags: Module with Connectors, Cryogenic. More details for QMC-CRYOCOUPLER-20 can be seen below.