The 2156-52-50 from KR Electronics (A Division of NIC) is a Low Pass RF Filter with Frequency DC to 52 MHz, Stopband Frequency 104 MHz, 3 dB Cutoff Frequency 52 MHz, Lower Rejection 40 dB@104 MHz, Upper Rejection 1 dB@104 MHz. Tags: Plug In. More details for 2156-52-50 can be seen below.