The 28-70-01A from TX RX Systems is a RF Duplexer with Frequency 450 to 470 MHz, Band 1 450 to 470 MHz, Power 350 W, Insertion Loss 1.5 dB, Isolation 50 dB (Between Channel), 90 dB (Per Channel). Tags: Rack Mount. More details for 28-70-01A can be seen below.