The SiMF25R37/R4-4W3 from Sainty-Tech Communications Limited is a Band Pass Filter with Frequency 25.17 to 25.57 GHz, Center Frequency 25.36 GHz, Insertion Loss 3.5 dB, Rejection 30 dB @24.5GHz&26.4GHz, 40 dB @24.2GHz&26.7GHz, 50 dB @DC~22GHz, 40 dB @27~35GHz, Upper Rejection 30 to 40 dB. Tags: Surface Mount, Cavity Filter. More details for SiMF25R37/R4-4W3 can be seen below.