The UIYDC4242A from UIY Inc. is a RF & Microwave Circulator with Frequency 250 MHz to 1.3 GHz, Bandwidth 367.5 MHz, Average Power Forward 300 W, Average Power Reverse 300 W, Insertion Loss 0.25 dB. Tags: Drop-in, Drop-in Circulator. More details for UIYDC4242A can be seen below.