I have a KFLa-400 (400HZ) roofing filter that I am selling for $50 plus shipping. Please contact me by email at w1ie at jetbroadband.com <mailto:w1ie at jetbroadband.com> with "Filer" in the subject line or my phone 540-583-0475 but keeping in mind of the time zones. USA purchasers only. With best regards, Jerry, W1IE