The SiMF3R7/1R3-7D2 from Sainty-Tech Communications Limited is a Band Pass Filter with Frequency 3.05 to 4.5 GHz, Center Frequency 3.7 GHz, Insertion Loss 2 dB, Rejection 30 dB @2.4GHz&5.4GHz, 40 dB @2.2GHz&5.7GHz, 60 dB @DC~1.5GHz, 60 dB @7~9GHz, Upper Rejection 30 to 60 dB. Tags: Surface Mount, Cavity Filter. More details for SiMF3R7/1R3-7D2 can be seen below.