The SiMS12R25/1R1-4D2 from Sainty-Tech Communications Limited is a Band Pass Filter with Frequency 11.7 to 12.8 GHz, Center Frequency 12.25 GHz, Insertion Loss 1.6 dB, Rejection 40 dB @DC~10.3GHz, 40 dB @14.1~20GHz, Upper Rejection 40 dB. Tags: Surface Mount, Cavity Filter. More details for SiMS12R25/1R1-4D2 can be seen below.