The KFF6666A from CTS Electronic Components is a RF Duplexer with Frequency 1.85 to 1.99 GHz, Band 1 1.93 to 1.99 GHz, Band 2 1.85 to 1.91 GHz, Power 2 to 20 W, Insertion Loss 3 to 3.8 dB. Tags: Ceramic, Surface Mount. More details for KFF6666A can be seen below.