I have one each of the following TT filters for sale: 1 model 288 1.8 khz 1 model 285 .5 khz 1 model 282 .250 khz Filters are in excellent condition and surplus to my needs. Will ship CONUS for $65 each. Please call me at 404 249-2498 days or 770 942-9911 evenings or e-mail. 73, Bob Durrell W4HT