The BFCN-3491+ from Mini Circuits is a Band Pass Filter with Frequency 2790 to 4370 MHz, Center Frequency 3489 MHz, Insertion Loss 1.5 to 3 dB, Upper Rejection 15 to 30 dB, Lower Rejection 18 to 21 dB. Tags: Ceramic, Ceramic Filter. More details for BFCN-3491+ can be seen below.