The SiMF4R05/R5-7D3 from Sainty-Tech Communications Limited is a Band Pass Filter with Frequency 3.8 to 4.3 GHz, Center Frequency 4.05 GHz, Insertion Loss 3.2 dB, Rejection 30 dB @3.4GHz&4.65GHz, 40 dB @3.3GHz&4.7GHz, 60 dB @DC~3GHz, 60 dB @4.8~10.6GHz, Upper Rejection 30 to 60 dB. Tags: Surface Mount, Cavity Filter. More details for SiMF4R05/R5-7D3 can be seen below.