The SiMF3R75/2R1-12D2 from Sainty-Tech Communications Limited is a Band Pass Filter with Frequency 2.7 to 4.8 GHz, Center Frequency 3.75 GHz, Insertion Loss 2.5 dB, Rejection 30 dB @1.95GHz&5.6GHz, 40 dB @1.55GHz&5.75GHz, 60 dB @6.5~8.5GHz, 60 dB @1.95GHz&5.6GHz, Upper Rejection 30 to 60 dB. Tags: Surface Mount, Cavity Filter. More details for SiMF3R75/2R1-12D2 can be seen below.