The FN-1289W from Filtronetics is a Low Pass RF Filter with Frequency DC to 200 MHz, Stopband Frequency 300 to 1000 MHz, 3 dB Cutoff Frequency 220 MHz, Insertion Loss 0.5 dB, Rejection 20 to 40 dB. Tags: Drop-In, Lumped Component Filter. More details for FN-1289W can be seen below.