The DEI9785-40.04MHz from Dynamic Engineers is a Band Pass Filter with Frequency 40.0295 to 40.0505 MHz, Center Frequency 40.04 MHz, Insertion Loss 2.5 dB, Rejection 50 dB@±40 kHz of Center Frequency, Ripple 0.5 dB. Tags: Surface Mount, Through Hole, Crystal Filter. More details for DEI9785-40.04MHz can be seen below.