The BFCN-4100+ from Mini Circuits is a Band Pass Filter with Frequency 3.7 to 4.5 GHz, Bandwidth 800 MHz, Center Frequency 4.1 GHz, Insertion Loss 1.4 to 2 dB, Power 1.5 W. Tags: Ceramic, Surface Mount, Ceramic Filter. More details for BFCN-4100+ can be seen below.