The SiMF3R8/R7-6E2 from Sainty-Tech Communications Limited is a Band Pass Filter with Frequency 3.45 to 4.15 GHz, Center Frequency 3.8 GHz, Insertion Loss 2 dB, Rejection 30 dB @2.9GHz&4.9GHz, 40 dB @2.7GHz&5.4GHz, 60 dB @DC~2.2GHz, 60 dB @6.3~11.3GHz, Upper Rejection 30 to 60 dB. Tags: Surface Mount, Cavity Filter. More details for SiMF3R8/R7-6E2 can be seen below.