The SiMF3R5/1-8D2 from Sainty-Tech Communications Limited is a Band Pass Filter with Frequency 3 to 4 GHz, Center Frequency 3.5 GHz, Insertion Loss 1.8 dB, Rejection 30 dB @2.65GHz&4.4GHz, 40 dB @2.55GHz&4.5GHz, 60 dB @DC~2GHz, 60 dB @5~9GHz, Upper Rejection 30 to 60 dB. Tags: Surface Mount, Cavity Filter. More details for SiMF3R5/1-8D2 can be seen below.