The SiMS9/R4-6D4 from Sainty-Tech Communications Limited is a Band Pass Filter with Frequency 8.8 to 9.2 GHz, Center Frequency 9 GHz, Insertion Loss 3.5 dB, Rejection 30 dB @8.3GHz&9.6GHz, 40 dB @8.1GHz&9.7GHz, Upper Rejection 30 to 40 dB. Tags: Surface Mount, Cavity Filter. More details for SiMS9/R4-6D4 can be seen below.