The DEI9812-21.40MHz from Dynamic Engineers is a Band Pass Filter with Frequency 20.1 to 22.7 MHz, Bandwidth -400 KHz, -2600 KHz, Center Frequency 21.4 MHz, Insertion Loss 4 dB, Rejection 40 dB @ - 4000 KHz, 700 KHz. Tags: Crystal Filter, Suspended Substrate Filter. More details for DEI9812-21.40MHz can be seen below.