The 2789 from KR Electronics (A Division of NIC) is a Low Pass RF Filter with Frequency DC to 40 MHz, Stopband Frequency 52.5 MHz, 3 dB Cutoff Frequency 40 MHz, Lower Rejection 84 [email protected] MHz, Upper Rejection 1.5 [email protected] MHz. Tags: Module with Connector. More details for 2789 can be seen below.