The BP0BA3900A7 from KYOCERA AVX is a Band Pass Filter with Frequency 3.755 to 4.058 GHz, Center Frequency 3.9 GHz, Insertion Loss 2.2 dB, Rejection 30 to 40 dB, Upper Rejection 30 to 40 dB. Tags: Surface Mount, Ceramic Filter. More details for BP0BA3900A7 can be seen below.