The SiMF18/1R4-6D2 from Sainty-Tech Communications Limited is a Band Pass Filter with Frequency 17.1 to 18.8 GHz, Center Frequency 18 GHz, Insertion Loss 2 dB, Rejection 30 dB @15.85GHz&19.75GHz, 40 dB @15.5GHz&19.95GHz, Upper Rejection 30 to 40 dB. Tags: Surface Mount, Cavity Filter. More details for SiMF18/1R4-6D2 can be seen below.