The 28-70-02B-U 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 0.6 dB, Isolation 46 dB (Between Channel), 100 dB (Per Channel). Tags: Rack Mount. More details for 28-70-02B-U can be seen below.