The T1AK4 from Sonoma Scientific is a RF & Microwave Isolator with Frequency 1.62 to 1.68 GHz, Average Power 1 W, Average Power Forward 1 W, Insertion Loss 0.5 dB, Isolation 23 dB. Tags: Drop-In, Drop-In Isolator. More details for T1AK4 can be seen below.