The SiMS12R45/R4-8D4 from Sainty-Tech Communications Limited is a Band Pass Filter with Frequency 12.25 to 12.65 GHz, Center Frequency 12.45 GHz, Insertion Loss 4.7 dB, Rejection 30 dB @11.8GHz&13.05GHz, 40 dB @11.7GHz&13.1GHz, 55 dB @DC~10GHz, 55 dB @14~24GHz, Upper Rejection 30 to 55 dB. Tags: Surface Mount, Cavity Filter. More details for SiMS12R45/R4-8D4 can be seen below.