The RCF-3750.000-900000-2012-W-001 from Raltron is a Band Pass Filter with Frequency 3.3 to 4.2 GHz, Insertion Loss 1.4 to 1.6 dB, Rejection 35 to 40 dB / 15 to 30 dB, Upper Rejection 15 to 30 dB, Lower Rejection 35 to 40 dB. Tags: Surface Mount, Ceramic Filter. More details for RCF-3750.000-900000-2012-W-001 can be seen below.