The ATEK859N4 from ATEK MIDAS is a Band Pass Filter with Frequency 37.5 to 40 GHz, Bandwidth 2500 MHz, Center Frequency 38750 MHz, Insertion Loss 5.2 to 6.1 dB, Lower Rejection 40 to 52 dBc @20 GHz, 34.1 GHz. Tags: Surface Mount. More details for ATEK859N4 can be seen below.