The DEI9840-21.65MHz from Dynamic Engineers is a Band Pass Filter with Frequency 21.638 to 21.662 MHz, Bandwidth 24 kHz, Center Frequency 21.65 MHz, Insertion Loss 4 dB, Rejection 60 dB@±80 kHz of Center Frequency. Tags: Surface Mount, Through Hole, Crystal Filter. More details for DEI9840-21.65MHz can be seen below.