The RADCC-4.5-6.5-Cryo-0.01-4K-S23-1WR-ss-b from Raditek is a RF & Microwave Circulator with Frequency 4 to 8 GHz, Average Power Forward 1 W, Average Power Reverse 1 W, Insertion Loss 0.4 to 0.8 dB, Isolation 18 to 36 dB. Tags: Coaxial Circulator. More details for RADCC-4.5-6.5-Cryo-0.01-4K-S23-1WR-ss-b can be seen below.