The 3TNF-250/500-N/N from K&L Microwave is a Tunable Filter with Frequency 250 to 500 MHz, Bandwidth 3 to 7 MHz, Rejection 40 dB @ 300 KHz, Input Power 50 W, Insertion Loss 0.5 dB. Tags: Benchtop, Mechanically Controlled. More details for 3TNF-250/500-N/N can be seen below.