The 28-56C-02A from TX RX Systems is a RF Duplexer with Frequency 380 to 420 MHz, Band 1 380 to 420 MHz, Power 250 W, Insertion Loss 0.7 dB, Isolation 50 dB (Between Channel), 100 dB (Per Channel). Tags: Rack Mount. More details for 28-56C-02A can be seen below.